I would second that. I ran M2s and a big sub for a while and it was terrific. I like M60s for music though -- still can't seem to get "mains + sub" to sound like a good full-range speaker.

Actually your suggestion is almost exactly the path I followed over the course of a year. First M2s and a sub, then M60s, then VP100, and I'll be picking up the QS8s tonight.
M60ti/VP180/QS8/M2ti, SVS PC-Plus 20-39, EP500
M5HP, Sierra-1, M40ti
M3v4, VP100