tough choice, depense on what you want...
M5 - pure performance, best handling, v10 f1 engine with high redline
CLS - pure luxury, heavy car, shit handling, more pimp
if you love to drive, and love performance then get M5
if you just like to relax, don't care about handling and want more looks get CLS
btw, i saw a video how new M5 walked e55amg, and I believe cls is slower then e55amg... also don't forget that bmw more reliable then benz, either way good luck, i'm sure you'll be happy with either one
