By 90 degrees, I mean directly left or right of the listening position. Say you're facing the front speakers, with 0 degrees straight ahead. Hold you arms out sideways -- that's 90 degrees. Directly behind you is 180 degrees.
Re ceiling mount of QS8s, I never actually did this, but planned on using the standard brackets, not FMB. Axiom said the standard bracket is safe for this, altough I have my doubts. Mine would have been mounted at a 45 degree knee wall (kind of a cross between ceiling and wall), so maybe that would have been OK.
For me it's a moot point since I ultimately used the QSS stands.
