I'm sure the CLS63 would be a great car but it doesn't seem to fall into the same class as an M3. The upcoming Gran Coupe ///M or M5 might be a better comparison.
It just depends on what your budget is and what is your intended purpose. If you have no desire to track, then the cls63 is a fine highway monster dressed in a Armani suit. If you want some track duty and prefer a lighter/smaller/cheaper vehicle the m3 is the way to go.
AngelinIsRich08: Just curious--how does the MCT feel compared with DCT? Based on magazine reviews, MCT got high marks but I know it is NOT a true dual clutch system.
2011 e90 M3 | SSII | FR | ZCP | DCT | Full Akra Evo | AngeliBright