I agree with JC!
I tried both M22s and QS8s as height speakers and felt the QS8s sounded better. All that comes from the high channels are ambient sounds which the QS8s are better at diffusing out around the room.
Something to consider is trying out wide speakers assuming you have the room for them. Depending on your room size/shape and the layout of your 7.1 speakers and seating you may find as I have that wide speakers offer a more significant improvement in soundstage than height speakers. Also wide speakers come into play during almost everything while the height speakers only really shine when there are ambient sounds like rain, echoes wind whereas the wide speakers are constantly playing something tending to better help the mains blend with the surrounds.
I now only use my height speakers for some music (stuff with lots of ambiance) and use my wide speakers for all other applications.
