Neither projector offers much range in their zoom lens. The BenQ, though, will work in some rooms in a rear shelf situation, if the room/screen match up for the right distance. The Optoma needs to be ceiling mounted (or table top), as it lacks lens shift.
Both of these projectors really do produce a really excellent image, and, important to many, they are the two brightest. For those fighting a little ambient light, they have an nice advantage. I should point out that the JVC easily matches their brightness in best mode, but when you need lumens for ambient light, the JVC can barely reach 900 lumens in Dynamic mode, while these two projectors can be 20 - 30% brighter, and that means a screen size or two larger. I could certainly live happily with either of these two projectors, if I hadn't seen the RS1.