If you believe that the Audi's torque advantage with make it a faster car in the STRAIGHTS, you are very ill-informed about high performance cars.
The 0-60 and 0-62 sprint data is for people like you, that can't comprehend what it takes to propel a car forward with such velocity. The HP of the M vs. the lack of it on the S5 (414 vs. 354; with a greater disparity to the wheels because of Audi's extra diff.-and their inability to build a proper rwd car.) will make for a faster straight line acceleration. The lower weight and attention BMW has given to created a center mass between the bumpers, with far less overhang, currently yields a car as close to a mid engine car, without going to a mid-engine design.
The real test of a car's HP is the standard 1/4 mile. The S5 barely matches the E46's 1/4 mile times and trap speeds; the E92 M will simply WALK away from it.
Even the 0-100 is indicative of a car's HP. The M has run that sprint in the low 10 sec. range. The only advantage the S5 has is it's launch by virtue of it's AWD. After the launch, the M will spank it. The RS5 IS another story, but as I mentionead above, it's going to be too expensive. And, it's more of a GT car than the M will be.
In the end, they are all beautiful cars, but, this BLINDLY BRAND LOYAL crap clearly illustrates what limited insight and/or foresight you have.