Welcome Mad, a couple of things worth considering would be if you were going with either of the standard finishes, it would be more economical to purchase B stock for your set up. This is what I chose to do for my so to be system . I inquired with Noreen at Axiom, about the general defects or flaws which is typically associated with B stock speakers. Noreen stated to me that more times than not, it's either visible excess glue about the drivers, or nicks or scratches on the drivers themselves. These are very small blemishes that can't be detected from greater than four feet away with the grilles off.
In my case I was debating between a projector, or a Mitsubishi 92" screen in my family room. Funds and future projector technology will make me wait before I go down that path, so the 92" is in my immediate plans. If I had gone with the projector though, I was going to go with dual M22's as my center channel. As cb919 has stated, some lean towards a vertical over a horizontal if possible. You have a capable power amp which would allow you to wire in series using only one channel. When it comes to audio able sounds, these bookshelf speakers are sup positively giant for their size. It would be possible to toe them out a bit for some great in room dispersion. You won't get a great deal of bass from this center channel set up, but in my option it won't be missed. Let the sub or subs do the heavy lifting. The M22's will then be responsible for clean, clear, crisp dialog which it can easily handle.
This option may or may not work for you in your space though. The price for two M22's would be much less than purchasing lets say a VP-180. This along with the first option, would save you several hundreds of dollars. Which you could then pocket, or might be used for that second sub you might be wanting. Any way you chose to go I believe you have gotten some great advice here on this thread. Good luck and good listening.
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