Hi asap.
I own both the M3ti and M2ti speakers. Each pair is used in a separate 2-channel audio system.
Of the two, my preference is the M3ti. It is the smallest and least expensive Axiom monitor that lets me enjoy the music without the need of a dedicated sub (not that a sub wouldn't help, mind you). The M2ti sounds stellar with a small sub; and on its own, a little light in the bass. .
Axiom's current pricing on the M2ti's is awesome, so I understand your dilemma in choosing.
Whichever monitor you choose, step up to the vp100 for home theater. Better sound and greater flexibility over the vp50.
Good luck!
-alan