Dude the news audis are so much pimper than the old ones you gotta love the v8 man! Shit, I live in Boulder so there are Audis fucking everywhere. In that regards, it sucks cause every rich spoiled kid here has a 1.8t a4 or and s4. However, I have seen a few rs4s around town and holy shit sickest exhaust note ever. 430 horsepower v8 from the factory beats a turbo 5 or biturbo 6 anyday of the week IMO. But yea Audi's are wonderful cars, kid I went to school with has an RS6 fucking spoiled bitch, and he can't even drive. I smoked him in a 540i sport like nothing.
To the guy that just bought that S4 good luck. Turbo 5 cylinder+110,000 miles+mods by previous owner would throw up some serious red flags to me. Anyways just stay on top of the maintenance and let those turbos cool down or you are gonna be knee deep in repair bills.