A bit more information might be helpful in consideration of your plans.
Your couch or chair positions, distance to your screen and front speakers, and rear speakers ? Is the floor carpeted, tiled, or wood covered ? Ceiling composition is ? What will the height of the speakers and screen be in relation to your sitting area ?
Wiring or cable connection: Some members prefer more treble in front with bass in back, and others the reverse. I prefer slightly more bass behind us watching programs, but these are all active speakers (4 x BL 4000), using a Beosound 4 as the dedicated driver of our HTPC.
Best suggestion: Take your time and try everything out, slowly and carefully. Rear speakers only, front speakers only, side and front bass. Note how they change from floor level to ear level when sitting, or when canted back at an angle. Despite what you see in the catalogues, nothing is permanent, so you can always change it whenever you want.