Well, this is and old discussion, probably over. I have rf7,rc7,fr7 front - rs-35s as side surrounds, - rb-35 rear surrounds. My room is relatively small, little over 2000 cubic ft. It is sort of funnel shaped. The wide end is my front/screen. That is about 15' wide. My projector is throwing about 120" wide image. My surrounds are close. I'm very happy with the sound from a pioneer elite sc-lx07.
Oh yeah, my projector is and 8700UB (1080p) but still love it.