I recommend you review my reply to KCMike in the recent post "Speaker and receiver selection".
I added several links in that post which you may like to read, especially the post in which i did a personal review of the M22s vs. QS8s as surrounds.

In regards to the issues about 'mandatory' stands for a QSx speaker, i do not use any at all.
My QS8s sit on a shelf and the other on a sidetable. Some others have also done this and to compensate for the downfiring woofer, i bought some one inch plastic 'furniture feet' from Canadian Tire and stuck them on the bottom of the QS8 to lift it a bit off the surface. The sound is just fine.

As for your idea about the multipole speakers firing into an 'empty' area, that IS the point.
The QSx speakers were designed to project sound into various areas and not directly at the sitting/listening position. This is exactly how they disperse sound and make the surround sound effect work. I can just about guarantee you will have alot more placement and tweaking issues by using direct radiating speakers for surrounds as opposed to a design like the QSx.

"Those who preach the myths of audio are ignorant of truth."