C63 is the best all rounder get with the performance package (includes a lsd not a electric trick diff) and it will hang with the m3 through the twisties. not to mention it sounds the best out of the 3. Maybe a 2-3year old e60 M5? or a E63?

 

M3 or IS-F.

you are going to end up with problems with the c63 and reliability.

 

get the ISF!

 

If all you care about is performance, then get the M3 or a motorcycle