I think I would bump up the sub to an EP500 other than that you have chosen a great system.

I think the QS8s will work great back there, just not quite as enveloping as when they are mounted to either side.

You could always pull extra wire down from those rear positions to the floor and run it around/under the base boards to the side position.


Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70