I am a bit uncomfortable steering you away from the M60s, but as good as the they are, they just can't provide the LFE that a sub can. I got my M60s on Friday (VP100/QS8s) to go with my SVS 20-39 PCi. I've been noodling around with and w/o sub. Gotta have the sub.
If my space wasn't so large (16x22x10 opening into a 14x20 kitchen), I would have gone with the M22s and let the sub do the heavy lifting.
As much as you might like to M60s (for sure, I love mine), for $800 you can pick up an awfully nice sub. I'd suggest looking at SVS or HSU - they usually end up leading the parade in the "What's the best sub?" threads on the net. Both companies have a customer service approach like Axiom and will talk to you at length to help you make the right choice. Whatever sub you might choose, make sure it is enough to avoid buyer's remorse. Talk to those folks and pick a sub that is big enough for your space such that it doesn't need to work at it's max capability to get you chest thumping LFE.
I also think you will find the QS8s are a much better choice for surrounds than the M22s.
