zzyzx, I would buy the full sytem try it out and if you truly do find an issue with the VP150 then you can return it and try to find another center that will be better and still fit where you want it to go. BTW, good luck with that, any center that does better than the VP150 is much bigger in the size, especially in depth and the ones I looked at were also much taller.
The idea of a bookshelf center works very well and eliminates the off axis issue, so if you can, I would try the M2 or even dual M2s, if you have the space and are truly concerned with the off axis issue, I have measured about a 1.5db drop in SPL going about 20-25deg off axis, but I still find the clarity to be about the same. I think it is just the volume drop that gives the impression of a lack of clarity. It's kind of like when comparing speakers of similar quality, if one speaker is calibrated higher than another, the louder speaker is usually deemed the better sounding one.
ctown, have you forgotten already, I have both VP centers and used them with the M22s and both work great.
