I've driven the 335i vs the RS4 backto back on a pretty good test route, about 6 miles each. The RS4 was much more fun, more entertaining, and had better sounds. The 335i more quiet and steady. I would "take" an RS4 over the 335i any day. but if I had to "buy" it with my own money, the $46,000 vs $70,000 is a BIG difference. you could get a 335i and a GTI for the RS4 price!