Thoughts on B&W CM5?

Well...one of my main speakers blew today. They're KLH model 6's and I do love them, but having them on 15" floor stands in the room does take up a fair amount of space. (they're gonna be fixed but moved to a secondary system I think)

Anyway.....

Would love to know your thoughts on the B&W CM5's? Amp currently is a Yamaha CA610 but am planning to upgrade that to a S1100 in the near future (maybe a bit later now given the speaker thing).

Actually, that being said.... would it be a horrible thing to place the speakers on top of an upright Kallax 4x2?