The bigger the speaker the better they push the sound into a room. as it appears it will be for Ht more than music I think the M3s and sub are the way to go although I think the M22s work a ittle better for HT as they are a little more forward and detailed than the M3s. They also will throw the sound out a little better than the M3s in the bigger room.

The sub is a must for HT use otherwise I would go for the floorstanders.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70