performance. i have a 3.2 l a3 now, and am thinking i may hold off. Tough choice... what year are you looking at in the S5? 2010? Coupe or cab? IMO, the S5 is a much better looking car than the S4 (which is just not aggressive looking enough for me). The B8 S4 with the 3.0T is quicker stock and has MUCH better tuning potential then the S5 with the 4.2V8. Also, from what I have heard, the new sport diff in the B8 S4 is great. The S5 coupe with the 3.0T (like the S5 cabriolet has) would be a great combination. How important is performance to you vs aesthetics?