Personally, I think the C63 and M3 are so close in performance, that it comes down to personal preference. I know that I would never look at a C63 and think, omg my M3 is soo much better. They are both incredible cars and it comes down to what is more important to the buyer. Either way, I would be very happy to have either one.
DailyD- Alpine White '08 E92 M3 Coupe Loaded w/ ALL, but w/ 6MT - *4 real men* 19" Wheels- 1xJL Audio 12w6v2 in H.O. box- JL 500/1v2-2 Farad Digital Hybrid Cap w/sub volume & bass boost controls mounted under dash! Blk Kdny Grls + more 2 come! *Sold! -'01 E46 Cosmos Blk M3 w/99,997 HARD miles on it! *Coming soon -911C2S/C4S,or C63AMG. Choices! AMG is Beast of difernt flavr even my GF could drive,where Pcar is similar 2 my current M3