Hi Fredk and Mike,
At the risk of further confusing the issue, while the idea of three identical speakers across the front is appealing, the practical reality is that because of specific placement issues and the vagaries of an individual room, using an identical speaker as a center channel won't guarantee that it will tonally sound identical to its left and right-channel mates, especially if you use pink noise as a test signal.
Pink noise (the standard test signal built into most AV receivers) is extremely critical. If you switch between left, center, and right using say, three M2s or three M22s, in most rooms and setups the tonal balance will vary, which many enthusiasts initially find disconcerting. The upside is that all Axiom speakers, including the VP100 and VP150, are tonally very close and with some experimentation in placement will produce a seamless blend with music or movie soundtracks.
I can't really tell you whether you'd prefer the sound of an M2 or M22 over a VP100 or 150 used as a center. With a proper A/B switching setup, you might conclude that they are so close in tonal balance as to be called "similarly good". I do not think you'd be disappointed using either the VP100 or an M2 as a center.
Regards,
Alan
