The Electrified Apex Predators: Unpacking the BMW M5 Touring vs. Mercedes-AMG C63s E-Performance – An Expert’s Verdict
In the rarified atmosphere of high-performance automotive engineering, where horsepower figures regularly eclipse four digits and acceleration times blur the line between asphalt and warp speed, a seismic shift is underway. For a decade, I’ve navigated the complex currents of the automotive industry, witnessing firsthand the relentless march of electrification. Yet, when it comes to the visceral thrill of a truly engaging driver’s car, the infusion of batteries and electric motors doesn’t always follow a linear path to improvement. This paradox is starkly evident in the latest clash of titans from Germany: the BMW M5 Touring vs. Mercedes-AMG C63s E-Performance.
These aren’t just cars; they are statements—bold, technological declarations of intent from two of the most revered performance divisions on the planet. Both represent the pinnacle of their respective brands’ current performance hybrid strategies, designed to reconcile raw power with increasingly stringent environmental mandates. Yet, their approaches, as I recently experienced across hundreds of miles of diverse driving conditions, couldn’t be more divergent, leading to a surprisingly clear preference for one in the ultimate test of driver satisfaction.
For years, the enthusiast’s mantra has been “more power is always better.” However, in the realm of modern performance vehicles, particularly with the advent of plug-in hybrid electric vehicles (PHEVs), this simple equation is now complicated by the undeniable physics of mass. Carmakers are grappling with the challenge of integrating substantial battery packs and electric motors into their most cherished performance flagships, vehicles that have traditionally celebrated lightweight agility alongside brute force. The result? A new breed of performance hybrid sedans that, while astonishingly quick in a straight line and capable of meaningful electric-only range, often struggle to replicate the nuanced handling dynamics of their purely internal combustion predecessors when pushed to the limit.
My journey began with the new G99 BMW M5 Touring, a machine of formidable presence and undeniable heft. From an engineering standpoint, BMW’s solution to electrification is uncompromisingly maximalist. Under its sculpted hood lies a potent 4.4-liter twin-turbocharged V-8, an engine renowned for its character and prodigious output, now augmented by a substantial electric motor and a sizable 22.1 kWh battery pack. The combined system output, officially rated at 717 horsepower and 737 pound-feet of torque, feels, if anything, understated. Independent dyno tests whisper of closer to 800 hp at the crank, translating to an almost alarming shove that pins you into the exquisitely crafted M sport seats, whether launching from a standstill or executing a rolling acceleration. The powertrain is, unequivocally, a masterclass in brute force, delivering relentless, instantaneous thrust that satisfies the most ardent speed demon.
What truly surprised me about the M5 Touring was its unexpected duality. The integration of the electric motor within the eight-speed automatic gearbox allows for genuinely brisk progress in EV mode. With 197 horsepower and 206 lb-ft of torque solely from the electric motor, this 5,456-pound luxury sports wagon can glide silently through urban environments with surprising alacrity. The subtle, piped-in acceleration sound adds a touch of digital theater, and even the “shifts” in EV mode—simulated through torque intervention—enhance the sensation of mechanical engagement. The all-wheel drive system ensures confident traction in all conditions, making it a surprisingly enjoyable and capable daily driver for city commutes, devoid of the V-8’s roar.
Yet, this impressive versatility comes at a cost, and it’s one that becomes glaringly apparent when the road turns twisty. The sheer mass of the M5 Touring is its Achilles’ heel. Heavier even than its all-electric sibling, the i5 M60, BMW has had to engineer a suspension system capable of managing this colossal inertia. The result, in my expert opinion, is a ride quality that borders on inconsistent, almost schizophrenic. One moment, it feels like a plush, cosseting grand tourer, soaking up imperfections with refined disdain; the next, it translates mid-corner bumps into an unsettling, almost alarming jolt. It’s a dynamic personality crisis that undermines confidence when driving spiritedly. Threading the M5 through a series of demanding curves feels akin to an athlete competing with ankle weights—the latent power is there, but the agility is hampered, with an uncomfortable amount of inertia constantly threatening to pull the car into understeer. This isn’t the fluid, telepathic connection M cars are famed for; it’s a constant battle against physics.
After spending considerable time wrestling with the M5’s weight, transitioning into the Mercedes-AMG C63s E-Performance was a revelation. Yes, it belongs to a different size class; it’s a compact performance sedan, not a full-size wagon. But the contrast in engineering philosophy, particularly concerning mass management, illuminated the M5’s shortcomings with stark clarity.
The C63s E-Performance has been a lightning rod for controversy since its announcement, primarily due to its departure from the traditional AMG V-8. Instead, it sports a highly advanced, hand-assembled 2.0-liter turbocharged four-cylinder engine—the very same M139 unit found in AMG’s compact segment dynamos like the CLA 45, but here, it’s longitudinally mounted. This engine, a marvel of internal combustion engineering, produces well over 400 horsepower on its own. It’s paired with a sophisticated electric motor integrated into the rear axle, an electric supercharger working in concert with a large turbocharger, and a comparatively small 6.1 kWh battery. The combined output is a staggering 670 horsepower and an even more impressive 752 pound-feet of torque.
Crucially, this entire package resides in a vehicle that is approximately 880 pounds lighter than the M5 Touring. That weight difference is not merely a number on a spec sheet; it’s a palpable force multiplier. When you engage “Race Start” in the C63s, the sensation of acceleration is unlike anything I’ve experienced in a combustion-engined car. The synergy between the instantaneous electric torque and the brutally efficient four-cylinder engine, bolstered by the electric supercharger eliminating turbo lag, creates a surge that feels profoundly faster than its paper specifications suggest, even outstripping the M5’s sensation of speed. The all-wheel-drive system flawlessly translates this immense power into forward motion, leaving nothing on the table.
Beyond the numbers, the C63s E-Performance offers a more engaging, more special driving experience. Popping the hood reveals not an anonymous plastic cover, but a proudly displayed, hand-signed plaque from the AMG technician who assembled the engine, alongside the visible architecture of the turbo and electric supercharger setup—a far more compelling sight than the M5’s hidden hot-V design. While some purists lament the loss of the V-8 growl, the C63s’ exhaust note, even with piped-in enhancement disabled, is characterful, punctuated by the thrilling sounds of the turbo building and releasing pressure. For an enthusiast, this mechanical symphony adds an extra layer of enjoyment.
Where the C63s truly excels, however, is in the corners. Unlike the C63s of old, which were notorious for their tail-happy theatrics, this new generation feels like a precision instrument. Its lower mass, combined with the rear-axle-integrated electric motor allowing for sophisticated torque vectoring, means it flows through bends with an alacrity that puts the M5 to shame. It doesn’t fight its weight; it leverages its relatively lighter footprint and advanced electronics to deliver exceptional corner-exit speed and minimal drama. This is the hallmark of a true driver’s car—one that inspires confidence and rewards skilled inputs with immediate, gratifying responses.
The fundamental philosophical divergence between these two performance hybrid sedans is profound. BMW, with its larger battery and emphasis on substantial electric-only range, appears to be targeting a broader definition of efficiency alongside performance, almost as if catering to regulatory requirements first, and enthusiast demands second. Its 22.1 kWh battery allows for dozens of miles of EV driving, contributing to a theoretical WLTP efficiency rating of nearly 150 mpg (though real-world EPA ratings, around 13 mpg combined, paint a far more accurate picture for sustained spirited driving). This “maximalist” approach inevitably leads to significant weight penalties.
Mercedes-AMG, on the other hand, adopted a “performance-first” hybrid strategy with the C63s E-Performance. Its much smaller 6.1 kWh battery, while meeting regulatory minimums for PHEV classification and offering a token 5 miles of electric range, is primarily designed to act as a performance booster. This judicious use of battery capacity minimizes weight, ensuring the electrification serves to enhance, rather than hinder, the car’s dynamic capabilities. This approach aligns more closely with performance-focused PHEVs from the likes of Ferrari (such as the 296 GTB and SF90, with their sub-8 kWh batteries), where efficiency is a secondary benefit, not the raison d’être for electrification. The result is a car that, even with a depleted battery, still returns a respectable EPA-rated 20 mpg, an impressive figure considering its ludicrous acceleration capabilities and its status as a high-performance vehicle.
This brings us to a crucial point about the evolving landscape of high-performance PHEVs. As an industry expert, I’ve observed that the people who invest in luxury sports wagons or premium performance sedans like the M5 Touring or C63s E-Performance are rarely swayed by theoretical fuel economy figures. They can afford to fuel their machines. Their primary motivation is the driving experience, the prestige, and the sheer exhilaration these vehicles offer. While electrification undoubtedly enhances efficiency to some degree across all applications, an overly large battery pack, designed to chase ambitious but often unrealistic efficiency targets, can ironically make a performance PHEV less engaging, and in some driving scenarios, even less efficient overall, than a purely combustion-engined counterpart due to the added mass.
The M5, despite its colossal power and technological prowess, feels like it’s trying to be too many things at once. It’s an incredibly fast, luxurious cruiser, capable of silent electric running, but it compromises too much on the nuanced agility and driver connection that defines a true M car when the roads get interesting. For someone seeking the ultimate driver’s machine in this segment, especially one valued for its dynamic prowess, the weight becomes an insurmountable hurdle.
The Mercedes-AMG C63s E-Performance, in contrast, despite its initially controversial four-cylinder heart, represents a more astute application of performance hybrid technology. It accepts the reality of electrification but tailors it to its core mission: to deliver an unadulterated, thrilling driving experience. It feels more special, more cohesive, and ultimately, more rewarding behind the wheel. The industry is still grappling with the optimal integration of electric power into high-performance PHEVs, and AMG’s minimalist, performance-oriented battery strategy offers a compelling blueprint for the future of such vehicles, emphasizing that true innovation lies not just in adding power, but in intelligently managing the entire package. When you’re talking about premium performance hybrid vehicles, the sum of the parts and their dynamic synergy is what truly matters, not just headline-grabbing numbers.
For anyone considering an investment in these cutting-edge performance hybrid sedans, the choice boils down to priorities. If your focus is absolute straight-line speed, luxurious comfort, and significant electric-only range for daily duties, with spirited driving being a secondary consideration, the BMW M5 Touring offers an impressive, if dynamically compromised, package. However, if your ultimate desire is for a truly engaging, agile, and confidence-inspiring driver’s car—a machine that connects you viscerally to the road and makes every twist and turn an exhilarating event—then the Mercedes-AMG C63s E-Performance stands out as the superior choice. It proves that in the electrified era, less battery, intelligently deployed, can indeed lead to a more profound and satisfying performance experience.
The future of performance hybrid sedans is undeniably electric, but the journey to true driver engagement in this new paradigm is paved with careful engineering choices. Having navigated the evolution of hybrid sports car reviews for a decade, my experience unequivocally points to the C63s E-Performance as the more successful execution of the performance PHEV concept.
Are you ready to experience the future of high-performance driving for yourself? Explore the nuanced differences firsthand by scheduling a test drive at your local luxury car dealership or delving deeper into comprehensive specifications and expert comparisons. The conversation around electrified performance is just beginning, and your journey into understanding these incredible machines starts now.
