I want to move from a 2.0 speaker system to a 5.1. Ideally, I'd like to keep the 2 main speakers I have -- a pair of Bowers and Wilkins CM5s-- because they are much nicer than what I can afford. (They are hand-me-downs -- thanks Dad!). But that means buying different brands at a lower budget for center speaker, subwoofer, and surrounds. Any recommendations on how best to do that? (FWIW i'm probably going to have to go with in-walls or in-ceilings for the surrounds, which is another wrinkle.) Is it better for me to just ditch the B&W's and go all lower budget if I can match brand? Or mix in other speakers for the other four speakers? I might just barely be able to justify getting a B&W 600 series centre speaker so at least the center has some match to the sides. But the CM series is definitely more than I can afford on my own.