FWIW,
Your front speakers will probably have the most impact on your overall system performance, particularly if you decide to stay with inwall options for your surrounds.
I would think an in wall speaker solution will not create a front "sound stage" as accurate or pleasing to the ears as free standing speakers can.
"Sense of depth - breadth - placement of sounds" within the front sound stage.
Given the option to go with bookshelves and a center speaker that is not wall mount. The Polk Lsi-9 series bookshelf speakers and matching LSiC can be found online for around 1K delivered = 650 + 350. (1500.00 retail)
The LSi series speakers have gotten excellent professional and owner reviews since their arrival in the market place over a year ago, generally compared to speakers costing 2 or 3 times this price.
Your rear sound field is generally fill and supporting sound effects yet the effects are quite often full range and require a speaker capable of reproducing fairly deep bass and reproducing a decent rear sound stage for accurate placement and sound effect pans between the front and rear. Wall mount rear speakers may be preferable since a voice or sound effect coming from a ceiling speaker may sound entirely out of place.
There are some excellent choices available within the ceiling and wall mount speaker arena. Polk Lsi - Mirage - Niles - NHT - Boston Acoustic - Klipsch - B&W - M&K - most major mfr.’s.
get out and demo some some surround flicks and tunes. See if you can find a dealers demo area with overhead or wall mount surrounds and listen to them sitting on a couch - do they sound "right" up there ?
May be one other thing to consider - possible rearrangement of furniture within a space having an impact on initial installation placement causing you to need to reposition the speakers built in walls. Dry wall can be patched

www.accessories4less.com is an electronics closeout dealer of several brands. NHT - while not the cheapest or most expensive option, 2 pairs of in wall or ceiling for rear surround about 800.oo Add the new Outlaw LFM1 for 570.oo
A bit over budget . . . but one sweet sounding system.
Good luck and have fun in your search !


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My train wreck
My modest HT . .


[This message has been edited by Steve_C (edited November 17, 2003).]