To cope with the speed differential that exists between the RS6 and nearly everything else on the road, Quattro fitted the car with Brembo eight-piston calipers up front and single-piston jobs at the rear. These brakes shorten stopping distances the way the engine shortens distances on a map. From 62 mph, the RS6 stops in 2.6 seconds. Yet, for all its decelerative might, the brake pedal has a mushy zone at the top of its travel that gives one pause, particularly when a schoolbus pulls into the left lane. These brakes offer less initial bite than you'd anticipate, a presumption based on the steering's high level of resistance.
Much of the Audi's tautness results from a new chassis system called Dynamic Ride Control (DRC). Think of it as an active suspension without the cost or complexity. Entirely mechanical-hydraulic, DRC negates most pitch and body roll by sending hydraulic fluid to the unloaded side of the suspension when the loaded side is compressed. Under braking, for example, as the front end loads up, DRC compresses the rear, counter-acting pitch.
Although DRC takes the slack out of the car's transitions, it still can't give the RS6 the kind of connective tissue that runs through the BMW M5. DRC can't mask the fact that the RS6 feels a bit reluctant to change direction. But that's not entirely bad. It's what makes the RS6 such an unwavering ally at high speed.
Other deviations from the A6 lineup include sport seats, new gauges, swatches of perforated leather, matte-finish aluminum, and gray poplar. For all this, Audi will charge a whopping $82,000. The flagrantly wealthy among us will have to ask themselves: Is straight-line performance worth that much, especially when those speeds are largely theoretical? After all, the car's flash point can rarely be hit on American roads. And, unlike the fluid, ultra-versatile M5, the RS6 at times can seem merely a tool for outrunning airplanes. In the end, is the ability to say you own the world's fastest sedan that meaningful? Hell, yes!