I agree with JC here... I'd worry about the first reflections. I've done something similar to what he's referencing... here's an old pic:
I got the first two reflections off the side walls and the first off the rear. Then of course I've got the carpet and 6 cloth La-z-boy's too. Personally I couldn't really tell any difference in mine and it may be because of the carpet and cloth recliners, I just don't know. Or maybe it's that I just can't hear well... but it's done none the less.