I'm about to get a full set of Axiom speakers to set up 7.1 sound in my HT, but am still not zeroed in on exactly which speakers to purchase. My HT room is 20' x 20', but is a "great room" style which opens up to an area of another 500 square feet or so. The roof is slightly slanted, averaging 9' high or so (not a cathedral roof line). I'm thinking M80's, QS8's, VP150, with high wall-mounted M22's as back speakers might be a good way to go. BUT, maybe it would be a better idea to put a pair of QS8's in back rather than the M22's. Can anyone advise? Note that sound quality is the major factor in making this decision, not cost.