BD, welcome. The advantage that the M60s would have would be entirely in bass extension and maximum bass loudness. A good sub takes care of the bass extension and provides more loudness capability for the majority of the bass range. The mid-range and treble are handled by the same drivers in both speakers, but note that the M22 has two of the 5 1/4" drivers handling the crucial mid-range, while the M60 uses one. If anything, therefore, the M22 would be able to play the mid-range frequencies a bit more loudly or with lower distortion at the same loudness level. It isn't necessarily true that a tower speaker can "play louder" than a bookshelf model in a large room.
My suggestion would be to go with the M22s plus a good sub.
