Don't hold me to this, but I think it was Alan (Axiom's resident expert) who said if you have only one rear surround speaker (6.1) it should be a QS4 or QS8. With one direct radiator in the rear, it's sound seems to come from the front rather than the back. If you're doing 7.1, then direct radiators in the rear are preferable.

Folks, did I remember hearing this correctly?

Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton