If you want a good reference point before making a buying decision find a store that sells B&W in-wall speakers. Take your favorite DVD or CD and have a listen. They sound very, very good. If you feel they might be out of your price range then at least you have a really good quality reference by which you can judge other speakers!
Find nearest dealer: http://www.bowers-wilkins.com/display.aspx?infid=1426
B&W in-wall speakers are called "Custom" series.