I vote QS4's.
My second choice would be the in wall M2.
And...I would have my rear surrounds inline with the knees of the back row viewers/listeners and approx 5' off the floor. The surrounds would be inline with the front row users knees at the same approx height.
This has worked in my narrow rooms very nicely.
The QS8 works beautifully too.

Last edited by brwsaw; 03/01/15 01:23 AM.