Always a tuff decision, but it biols down the following IMHO:
1)Likelyhood of moving your system to a bigger room at some point. (some consider this a once in 20 year purchase some change every couple of years).
Most people will move and often upgrade their living condictions which may include a bigger room for your home theater. This is a good argument for for M80s.
M60's with VP150, Q8s and an EP500 is going to work extremely well in about any room short of huge. You'll also have more and cheaper options for quality receivers.
M22s I personally don't see as that great an option except in perhaps a bedroom system or if you are on a really tight budget. Even then I would probably go with M3's, VP100, Q4s and a rocket 10'.
That is my take anyway.
