Long time no see, Cooper. Your description of your room was pretty clear and indicates that the QS4s would be the better choice. Operating in rather close quarters it's even more important to select surround speakers with wide dispersion. If you mount them on the rear wall separated as widely as possible(they'll still be playing side surround material although they're on the back wall), say about 8' apart on the 9' wall, and 2-3' above ear level, you should get a nice mix of direct sound plus reflections from the ceiling and side walls.
One further suggestion once you get the surrounds set up is to make full use of them with all source materials. I never limit myself to using only the front speakers. Most of the sound reaching us at a concert comes as reflected ambience from directions other than the front. When the microphones picked this up it had to be mixed into the front channels in a 2-channel source. There was no choice as there was no place else to put it. Now, however, processing such as DPLII detects the phase differences in the mixed-in surround ambience, extracts it from the front speakers and sends it to the surrounds where it belongs, making the home listening experience a little more realistic. The degree of improvement varies with the amount of ambience mixed into each recording.
