I love these posts and really wonder why anybody would care what the faster car is??
IMO it should be really about which car you personally like better despite a tenth of a second here or there - Why would you care what anybody else is saying/writing about a car??.
Obviously for me it was the M3 a purpose built sports car with some real motor-sports DNA and not your average chick car with a big shouting exhaust and granted an awesome engine...I guess that the C63 is the perfect car if you are into the muscle car stuff, which IMO really is what it is. I bet the new Camaro that is supposed to come out in 2009/2010 is going to smoke both the C63 and M3 in straight line performance. Does the mean I would want to have one? Certainly not - there is more to a car than just performance numbers...
I also have to admit that I am really biased, since I was born and grew up in Munich and any real Bavarian would never buy a Merc