Your question could be better solved with some room dimensions, I have M22's and a cheap sub in a 12X16 room that is open at one end to 27' and the M22's fill it nicely with sound and the sub adds that extra little bit that the 22 don't drop down to.

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