I'd hang the rears from the ceiling using the Axiom full metal ceiling bracket. Unless that solution gives you wiring, aesthetic or cost problems. If that's the case, I'd do as Charles suggested and get some M2 or M3's for the wayback rear wall position instead. That might even make more sense depending upon how you're using the rest of the room - if you've got people spending time in that half of the room, you might like to have "all channel stereo" there rather than the diffuse sound of the QS series.
