Just look at the bare figures. 414bhp, a 0-62mph time of 4.8 seconds (4.9 seconds for the Avant and Cabriolet) and 430Nm of pulling power. But that's only half the story because the RS4 is one of the most exhilarating cars you'll ever drive. Acceleration is brutal but the car never feels flustered when being driven hard and thanks to the quattro four-wheel drive system traction is excellent, even in the wet.
In-gear performance is astonishing and the V8 unit will scream all the way up to 8,250rpm. In keeping with the performance image, the RS4 is only available with a manual gearbox which has a positive shift action and is a delight to use. The clutch isn't too heavy either making the RS4 easy to drive in traffic.
Thanks to a lower ride height than the standard car, plus stiffer suspension settings the RS4 is superb through corners with minimal body roll. A new system called 'dynamic ride control' helps matters further by counteracting pitch and body roll movements so the RS4 always feels planted to the road. Push hard and you can detect a little movement in the body but it's still incredibly involving to drive.
That doesn't make it intimidating though - and it can be equally effortless to drive day to day. The steering is light at parking speeds but nicely weights up on the move and offers good feedback plus with the latest electronic stability programme and immense brakes it always feels safe. The Cabriolet version doesn't suffer from any major lack of stiffness despite the roof being chopped off.
An upgrade is available on all RS4 models as an option ('sport suspension plus'), which lowers the ride height by a further 10mm and features stiffer springs and dampers.