The Electrified Anomaly: Why the Mercedes-AMG C63s E-Performance Outshines the BMW M5 Touring
In my decade of navigating the intricate landscape of high-performance automotive engineering, I’ve witnessed countless shifts, from the dominance of naturally aspirated behemoths to the turbocharging revolution, and now, the profound embrace of electrification. The automotive industry, particularly its performance division, is at an intriguing crossroads. Carmakers are grappling with the dual mandate of delivering electrifying speed while adhering to increasingly stringent global emissions standards. This delicate balancing act has given birth to a new breed of beast: the performance plug-in hybrid electric vehicle (PHEV). But as I’ve learned firsthand, simply cramming more power and larger batteries into a high-octane machine doesn’t automatically equate to an enhanced driving experience. In fact, it can sometimes dilute the very essence of what makes a performance car truly special.
This realization crystallized recently after an intensive back-to-back evaluation of two highly anticipated titans entering the 2025 model year: the G99 BMW M5 Touring and the Mercedes-AMG C63s E-Performance. These aren’t just cars; they are statements, design philosophies on wheels, each offering a distinct interpretation of what an electrified performance sedan (or wagon, in the M5’s case) should be. My time with these two vehicles didn’t just highlight their individual merits and shortcomings; it underscored a fundamental divergence in engineering philosophy that will likely define the future of this segment. While both deliver absurd straight-line speed and a degree of electric-only capability, the subtle yet profound differences in their hybrid architectures dictate profoundly different driving dynamics. In this expert review, I’ll dissect why one, despite seemingly being the underdog, captivated me far more than the other, and what this tells us about the best performance hybrid solutions for the discerning driver.
The Weight of Ambition: A Deep Dive into the BMW M5 Touring
Let’s start with the new BMW M5 Touring. On paper, it’s an absolute sledgehammer. Powering this magnificent wagon is a formidable 4.4-liter twin-turbocharged V-8 engine, augmented by a potent electric motor, culminating in a claimed system output of 717 horsepower and a staggering 737 lb-ft (1,000 Nm) of torque. Having personally pushed the limits of this machine, I can attest that these numbers, impressive as they are, might even be conservative. Dyno tests hint at real-world outputs closer to 800 horsepower, meaning the M5 Touring can unleash truly alarming pace, pinning you to your seat with relentless force, whether you’re launching from a standstill or executing a rolling overtake. The surge of combined combustion and electric torque is nothing short of breathtaking.
The M5’s powertrain, in isolation, is undeniably brilliant. BMW has integrated the electric motor within the eight-speed automatic gearbox, contributing 197 hp and 206 lb-ft of torque. This setup allows the M5 Touring to operate in a surprisingly capable EV mode, even in its hefty, 5,456-pound (2,475 kg) form. I confess, a significant portion of my enjoyment driving the M5 came from this electric-only experience. It’s quiet, smooth, and surprisingly brisk around town, enhanced by a subtle, almost sci-fi acceleration sound piped into the cabin. The system still simulates gear shifts even with the V-8 dormant, adding a layer of engagement I didn’t expect. Power is sent to all four wheels, ensuring reassuring traction in varied conditions, making it a genuinely practical luxury performance car for daily commutes, even in inclement weather.
However, after hundreds of miles behind the wheel, a peculiar thought began to surface: I found myself wishing I was driving the pure electric i5 Touring M60 instead. This sentiment, frankly, was startling, as it’s something I never anticipated from an M car. The new M5 is the first BMW M vehicle that didn’t immediately stir a sense of fervent desire in me. The culprit? Its sheer mass. This is where the M5 Touring’s ambition meets its significant drawback.
At over 5,400 pounds, the M5 Touring is heavier than its all-electric sibling. To manage this colossal weight, BMW’s engineers have had to tune the advanced suspension systems to their absolute limits, resulting in a ride quality that feels curiously unresolved. It struggles to decide whether it wants to be a cosseting luxury cruiser or a taut sports machine. On one hand, it can feel overly soft, like a Maybach attempting to float over imperfections. On the other, it can suddenly become jarringly stiff, akin to a pogo stick reacting violently to road undulations. This inconsistency in ride quality detracts significantly from the premium feel expected from an M car.
The impact of this weight extends catastrophically to the M5 Touring’s handling. Mid-corner bumps often unsettle the car, sometimes alarmingly so, leading to uncomfortable weight transfers that undermine driver confidence on twisty roads. The pervasive inertia makes the car feel like an athlete attempting to sprint with ankle weights on. When driven spiritedly, there’s an uncomfortable amount of understeer, forcing the driver to fight the car’s natural tendency to push wide. For a brand synonymous with “The Ultimate Driving Machine,” this feels like a fundamental misstep, highlighting the critical challenge of integrating large battery packs into high-performance vehicles without compromising the visceral driving experience. The trade-off for dozens of miles of electric range in a performance PHEV is simply too high for this particular application.
Agility Through Innovation: The Mercedes-AMG C63s E-Performance Deep Dive
Switching from the M5 Touring to the Mercedes-AMG C63s E-Performance was an immediate and profound revelation. While still a plug-in hybrid and therefore heavier than its purely combustion-engined C63 predecessors, the C63s felt dramatically more agile, putting the M5’s mass into stark perspective. Yes, it belongs to a size class below the M5, making it not a perfectly direct comparison, but the experience it delivered was simply superior. My verdict: I would unequivocally choose the C63s.
The initial criticism against the new C63s centered on its engine: a 2.0-liter four-cylinder, half the cylinders of the M5, and slightly less peak horsepower. But this isn’t just any four-banger. This is the M139 engine, a hand-assembled, bespoke AMG unit borrowed from the brand’s hottest compact offerings like the CLA 45. Lift the hood, and you’re greeted by the proudly displayed signature plaque of the engineer who built it, alongside an impressive visible setup featuring a massive turbo and electric supercharger technology. This sight alone felt more impressive than the M5’s plastic-shrouded, albeit clever, hot-V twin-turbo design.
The M139 on its own churns out well over 400 horsepower. Paired with its electric motor, the C63s E-Performance delivers a combined 670 hp and an astonishing 752 lb-ft (1,020 Nm) of torque. That’s more torque than the M5, in a car that’s approximately 880 pounds (400 kg) lighter. And you can absolutely feel every single pound-foot of that difference. The force exerted on your body during a Race Start in the C63s is unlike anything I’ve experienced in a combustion-engined car, period. It feels significantly faster than the BMW, even if the raw numbers suggest a closer contest. Both cars are quicker than their specs imply, but the C63s extends that margin considerably. Its instantaneous off-the-line acceleration, courtesy of immense torque and a highly effective all-wheel-drive system, is nothing short of shocking.
The electric supercharger technology plays a pivotal role in this responsiveness, building boost almost instantaneously and virtually eliminating turbo lag. The powertrain is incredibly reactive, and the seamless surge from the combined electric and gasoline mills is truly special. While some purists bemoaned the loss of the V-8 rumble, the C63s doesn’t sound as “bad” as rumored. Even with the piped-in sound enhancement deactivated, the genuine exhaust note is characterful, and the audible whoosh and whistle of the turbo building and releasing pressure adds a compelling, mechanical soundtrack to the fun. This visceral feedback, often overlooked in premium sports car reviews, significantly enhances the driving dynamics.
Crucially, the C63s is far more enjoyable through the corners than the M5 Touring. Unlike older C63s models, which were often tail-happy tire-shredders, this new iteration feels like a precise track performance tool, meticulously focused on delivering optimal corner exit with minimal drama. It’s planted, agile, and inspires immense confidence. While based on the smaller C-Class platform, which naturally provides a weight advantage over the G61 5 Series Touring platform used by the M5, Mercedes’ approach to its hybrid system is the true differentiator. There isn’t an E63 PHEV to serve as a direct competitor (yet), and the E53 plug-in hybrid, despite its widebody aesthetic, doesn’t operate in the same performance league as the C63s or M5. This highlights AMG’s deliberate design philosophy for the C63s: a lighter, bespoke system.
The Philosophical Divide: Performance PHEV Approaches
Herein lies the true genius of the Mercedes-AMG C63s E-Performance and the core philosophical difference between these two performance hybrid sedans. Unlike the M5, which utilizes a larger battery and motor configuration similar to lesser PHEV variants across BMW’s lineup, the C63s gets a smaller, purpose-built setup. Its electric motor isn’t integrated into the gearbox but is precisely positioned on the rear axle, and its primary purpose is not extensive EV range. While it can manage a modest 5 miles on electric power, its main objective is pure, unadulterated performance boost.
Mercedes’ key stroke of brilliance with the C63s was its battery strategy. The M5 Touring features a substantial 22.1-kilowatt-hour battery, a primary contributor to its immense heft. The C63s, by contrast, employs a mere 6.1 kWh battery. By conventional PHEV standards, this is tiny. However, it perfectly serves its purpose: to significantly enhance performance while providing enough electric capability to satisfy regulatory requirements, especially Europe’s increasingly stringent emissions standards. This smaller, lighter battery is the single most important factor enabling the C63s’s superior agility and responsiveness.
The impact on fuel efficiency and real-world usability is equally telling. The heavier, more powerful M5 Touring boasts a WLTP efficiency rating between 1.6 and 1.7 liters/100 km (nearly 150 mpg). This figure, however, is achievable only if the battery is consistently topped up – a practice many PHEV drivers neglect. Consequently, the M5’s EPA combined rating of 13 mpg (18 l/100 km) offers a much more realistic picture of its actual returns in typical driving scenarios.
The C63s doesn’t achieve such astronomical (and often unrealistic) WLTP figures, with a claimed average of 6.9 l/100 km (34 mpg). While achieving this requires an extremely light throttle foot, it is genuinely attainable even with a depleted battery. When driven in the spirited manner these cars are designed for, to truly enjoy the car rather than solely optimize for fuel savings, I observed around 15 mpg in the C63s. This is still excellent given its ludicrous acceleration. The EPA rates the C63s at 20 mpg with a depleted battery, a figure easily achievable without concerted effort towards hypermiling. These real-world figures underscore a critical point often missed in performance car market trends: for buyers of these luxury performance car models, advertised efficiency, while a technical achievement, is rarely a primary selling point. The ability to afford to fuel these vehicles means performance and driving experience take precedence.
My extensive experience in the high-performance vehicle financing and supercar alternatives segment teaches me that enthusiasts prioritize feel and engagement over abstract efficiency numbers that often don’t translate to their driving habits.
The Evolving Landscape of High-Performance Vehicles
This M5 Touring vs C63s E-Performance comparison serves as a crucial bellwether for the future of electrified performance. We are InsideEVs; we celebrate the power of electrons. But in the realm of truly high-performance vehicles, the adage “more is better” concerning battery capacity often rings hollow. The industry must make a clear distinction between electrified cars primarily designed for maximum efficiency and range, and those where electrification is meticulously engineered to enhance performance.
Mercedes-AMG’s philosophy with the C63s E-Performance aligns far more closely with what we see in true exotic performance PHEVs like the second-generation Acura NSX, the Chevrolet Corvette E-Ray, the Ferrari 296 GTB, or the new Lamborghini Temerario. In these elite machines, the battery isn’t a leaden burden but a finely tuned component in a complex system designed for instantaneous torque delivery and sharpened responsiveness. Ferrari’s plug-in hybrids, for instance, rarely feature batteries larger than 8 kWh in models like the SF90 and 296 GTB. This keeps the chassis unburdened, preserving the purity of their legendary handling. The few miles of electric range are a bonus, but the main point of electrification remains the relentless pursuit of performance.
A smaller battery also mitigates the risk of the “hamster wheel” effect, where a depleted battery forces the engine to divert precious power to recharge the pack. In my spirited half-hour drive of the C63s on a twisty road, I still had around 33% battery remaining. For all but sustained track laps at maximum attack, performance degradation due to battery depletion is a non-issue. This thoughtful engineering approach is a testament to AMG’s commitment to the driver.
Conclusion: The Expert’s Verdict
The automotive industry is in a fascinating phase of innovation, where automotive engineering pushes the boundaries of power and efficiency. However, the true test of a performance PHEV lies in its ability to deliver an uncompromised, exhilarating driving experience. The BMW M5 Touring, despite its colossal power and technological prowess, ultimately falters under the weight of its battery, leading to an inconsistent ride and compromised handling dynamics. It’s an engineering marvel, but not quite the driver’s car its heritage promises.
The Mercedes-AMG C63s E-Performance, by contrast, represents a more enlightened approach. By prioritizing agility and dynamic enhancement through a smaller, performance-focused battery, AMG has crafted a truly compelling and exciting machine. It feels more special, more connected, and ultimately, far more enjoyable to drive than the M5 Touring, even with half the cylinders. It’s a testament that sometimes, less battery can indeed mean more performance, more agility, and a far more engaging connection between car and driver. This is the blueprint for the best performance hybrid of the future.
If you’re ready to explore the cutting edge of electrified performance and experience a drive that truly redefines agility and power, I urge you to experience the Mercedes-AMG C63s E-Performance for yourself. For insights on luxury performance car lease options, performance car insurance, or to delve deeper into these remarkable vehicles, connect with a trusted high-performance automotive specialist today. Don’t just read about the future of driving; get behind the wheel and feel it.
