2005 BMW M5 vs. 2005 Mercedes-Benz E55 AMG Interior comparison

That isn't to write it off: As a Mercedes-Benz sedan, with all that entails, it's brilliant. Just using a fraction of the power, it's a car of immense authority and security, its torque and autobox lazing their way through the everyday, then ready to flick to a spurt of hyperdrive when called on. No one will say its cabin is anything other than tastefully furnished and immaculately made--look at the precision of those highlighting metal strips along the wood fillets. Check the moonish blue instrument backlighting. Feel the soothing ride as the airsprings switch to comfort mode.

The M5 is edgier in the quotidian grind. Although switching out of M mode helps by lengthening initial throttle-pedal travel, it's hard to be as smooth when there's no torque converter to dull the engine's response. And when making slow-speed shifts, the sequential box is good but not that good at slurring through the ratios: Unlike with the Audi DSG, you always have to spend some time in neutral. The basic spring settings of the M5 also give it a firmer ride than the E55's.

No 5 Series discussion can avoid the cabin. Is the furnishing clean, modern, and minimalist? Or plain sparse? There are more square feet of leather over the fascia and doors than in the Mercedes, but it's the Merc that sets a tone of plushness. Go figure. The notorious iDrive's graphics and speed of response are getting less clunky with each generation, but it can still take a lot of scrolling through menus before you locate and reconfigure several commonly altered functions. Yet the head-up display is a masterpiece, putting your speed, radar cruise information, and navigation turn arrows right where you need them. Truly that counts on the autobahn deep into three-figure speeds. And off the highway, we've already seen how cool it is to be given so clear a flag to finesse your gear-change points.

Because in those moments, the ones where you're in deep with the car, pushing this amazing engine and transmission to their limits--those are the ones where the M5 edges ahead of the AMG equivalent. Not actually because of the drivetrain itself, but because of what it lets you do. Explore the BMW's cornering. Explore the defining new M5 moment.