Hi gj47479! Many of us use different brand surround speakers in our HT set ups (I know I do). If it is mainly for movies, I think you'll be okay. Timbre matching is not so critical for that.

The QS8 speakers are excellent for surround use. I find them much more suited for surround duty than directional speakers.

You do have a pretty big room, but even so, I'd start with just one pair of QS8 speakers and see how well they do. If you feel you need more, you can always add a second set.

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"Nothin' up my sleeve. . ." --Bullwinkle J. Moose