In a straight-line no doubt, I agree, besides the Audi Turbo engines are easy to mod (no they are dropping the turbos for the atmospheric engines though) and extract plenty of HP, but thats precisely what I meant, fast in a straighline maybe, but thats not what Ferraris or Porsche are about, hence my sarcasm to the "feed me Porsches and Ferraris".
And specially not the nose heavy, understeering, overweight Audi "Quattro" station wagons. Torsen differentials is what the Hummer uses very heavy and do not allow for varying torque split between front and rear so they behave like front wheel drive cars, i.e. grippy and safe in very slipery conditions but not very sporty in the curves so not used in any sportcars... but the Mitsu EVO's active differentials or even Porsche's viscous coupling AWD is another matter and indeed an advantage in mountain pases with rough surfaces, but specially the EVO is a monster in that terrain better than a 911 I dare to say, though the 911 is a more complete performer more complete package... highways, track, mountain, etc.

Anything can be made to go fast in a staright line, even SUV's these days, but its not very amusing, the fun is in the bends IMO. But in staright-line highways, the Audi's are a force to reckon with as you say, besides many of them are modded. Fortunately in the highways here there are a lot of curves and no real straights, best highways in the world IMO! Maybe I should put in my bike's licence plate, RS4's for breakfast and ENZO's for lunch if its just about staright-line accel