m3 or m4

Hi guys, I know this is the Mercedes Benz club however having been a frequent observer you guys have a vast knowledge of other cars as well. So putting brand bias aside what would it be the c63 507 or the f80 m3/m4? It's a genuine choice I'm considering I can't split them at that price...

I have 6 months left now on my current deal and I am in the market for a C63 or the new M3/M4. I have previosly owned an E92 M3 Coupe but really not sure which way to jump. I have test driven the current C63 and loved it! The W205 C63 will not be available until sometime in 2015. So I could...

M3 Visualizer http://www.bmw.com/com/en/newvehicle...zer/index.html M4 Visualizer http://www.bmw.com/com/en/newvehicle...zer/index.html