Dave. On the M22 as center question, they certainly work as both Alan and I use them for this. From a frequency response perspective they have a slightly better bottom end than the VP150, however, from a power handling/volume perspective it is a different story.
The VP150 has a sensitivity of 91db and power handling of 400w vs 87db and 150w for the M2. The vp150 will play noticably louder. The M2 might be just fine in your room in a dual configuration. I would ask Alan. I suspect he will know.
Fred,
What do you mean "in a dual configuration" ? Do you mean wiring them together to get a 4ohm pair? I'd guess the sensitivity for dual M2' would still be 87dB. I'd worry that M80's with 95db, might overpower the dual M2 centers. I guess that is why you said... Check with Alan. :o)
