some knowledgeable people here on the forum so you might get good advice. But folks here are generally more into audio for music than home theater. Not much enthusiasm for in-wall or in-ceiling speakers, since they have compromises. (Plus, in my mind, what if you rearrange the furniture?!?) Try also home theater oriented forums.
(Kal R. tho, posts here sometimes, and knows tons, maybe he'll see this)

Check out Epos for speakers. I have some M12.2s as my front channels and their ELS3C center speaker and it sounds great. My back wall's are a somewhat lesser brand which I am debating whether to upgrade or not. Good for music server playback too. I do not recommend in-wall speakers. Never heard any I liked, although I have not heard all by any means. It's just that a little air around a speaker goes along way to better sound and realism.

Hello tpip. Epos makes good stuff. I have posted a link to a review of Definitive Technology speakers in The Perfect Vision, which I feel is the Stereophile counterpart for home theater (free on-line AV mag). They have a well-informed staff of audiophiles onboard. You could do worse than look up their past issues for reviews. They acknowledge that high end sound with in-walls is extremely difficult to obtain and they are pretty demanding of the equipment they review. Hope this helps.

inwall info