I like your idea with AT screen and 3 RB-61. My ceiling is very low (7'), and you mention a VERY good point about controlling reflection with the 90 x 60 horn vs 90 x 90. hmmm. With RB-61, i would have to orient them vertically, and not on side, under the screen. ok. What if I could fit them under the screen vertically? Concerns with AT screen: 1) "assumed" it degrades picture somewhat at our viewing distance (11 feet) but I don't know, since I've never had one to compare. 2) cost. I would like to do 100" wide screen (115" drag.), and need to stay under budget ($700).