1)Every movie has a different sound mix. Some movies constantly use the surround channels and LFE while others never use the surrounds or LFE.
2)The point of 5.1 is to have 5 full frequency channels of sound.
3)The Music formats are almost always more aggressive in their use of surrounds, but some can still be quiet in the surrounds and depends on the mix.
4) The QS8's will work better than anything for movies, I use them for DVD-A and they work incredibly well. So I would say go with the QS8's.
5) No, but why does that matter?

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