Hi eric916,
Just to add to the helpful answers already posted, the QS4s should be fine for your room size. The QS8s have slightly larger woofers and thus play louder and cleaner in big rooms. Tonally, the two are virtually identical.
The general advice I give on surround height for QS4s and QS8s is at least a couple of feet above ear level when you are seated. The QS8s and QS4s are so forgiving because of their multi-directional radiation pattern that you can mount them considerably higher if you like--anywhere from 2 feet to 8 feet above ear level and the surround envelopment does not change appreciably--but keep them away from the ceiling by at least 6 inches so you'll get some ceiling bounce from the top-firing woofer/midrange driver.
If your room is asymmetrical and does not allow for mounting the QS surrounds at equal heights, it doesn't matter. One of mine is 2 feet higher than the other and the surround envelopment is excellent.
You normally do not have to aim the QS models toward the listening area unless your room has a very high vaulted ceiling and you put the surrounds up much higher than usual.
Here's a link to my article in the Axiom archives with diagrams showing setups for 5.1 and 7.1 systems.
http://www.axiomaudio.com/home_theater_layout.html Regards,
