I would go with M3s given the size of your room unless you are going to only be listening at modest SPLs. They have a slight bass bump around 100-150 Hz as do most small speakers designed for standalone use but I don't think you will notice that very much.

The M2s are REALLY nice and extremely accurate (I ran a pair with sub for quite a while before upgrading to M60s) but the woofer is pretty small and that does limit the amount of "loud" you can get...

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8