I'm with Craig. If you buy the premise that QS8's are "better" for movies and that M2's are "better" for DVDA/SACD, then the question becomes which of those do you listen to more?
But I think the improvement in multi-channel music would be negligible compared to the amount of difference you would see in home theatre. I used to have cheap Boston direct-radiating surrounds, and was astounded by the improvement with the QS8's.
I don't think the lack of directionality in the QS8's is going to be meaningful unless you listen VERY critically to a LOT of multi-channel audio from the sweet spot.
