Mike, I don't have much of significance to add on that point. Since your centers above and below the screen already are anchoring the center channel material to the screen pretty well, there wouldn't appear to be room for improvement in that regard. Since the M22s are quite similar to the M80(and presumably VP180)above about 90Hz, there might be little overall sonic difference either.

Seeing Alan's reply which mentioned listening tests on various combinations, I'll ask about a test I wondered about. My thought on seeing the VP180 was to stand the poor thing upright in a more manly posture and it might perform even better. Were two upright VP180s compared with the M80s as mains, and what benefits/detriments were noticed if this was done?

Enjoy the music, not the equipment.