Josh, you do understand that your left/right surrounds should be just that, left/right of the listener. The only time you would want to place them on the rear wall is if you have no other options. Now for 7.1, obviously you would have rear channel speakers in addition to the left/right surrounds.
I also second Dan's question about Q series, for surround applications your never going to get the same experience out of direct radiating design. Oh yeah, they do darn good for music as well. Also, the Q series are going to be far more forgiving and easy to place for most situations.
M80s-VP180-QS8s-EP600-2xEP350 Denon3808 Outlaw7700
(M22-OWM22-VP100)-all in storage