While the M50s are very good speakers and seem to match your listening habits quite well(only 10% music)and yes, are the better priced set; there still is the question of what style of listening you are used to, or prefer?
As has been previously noted, there are differences, though slight, between the sound of the two floorstanders. And these differences should be well understood before deciding.
That said....
I can't recall anyone using the VP150 with M50s, but I do know that the VP100 has been, and is being used with them with great satisfaction. I'm not sure that your room is large enough to require a VP150, although it certainly wouldn't be overpowered by one.
Other folks are using M2s and M3s as centers with good results. The M2 would be best suited for use with M22s and M60s(it would be a stretch to add M80s to the list!!)and the M3s go well with M50s.
