Thanks in advance for the good advice and feedback. I have been lurking around for a few months.
Room - 15 X 19 X 8, and is a multi-purpose room (I am jealous of the hall passes some of you have received to build these awesome HTs), The TV is on the 15 side and viewing area is about 10 feet from the screen.
I recently ordered M60's for fronts, and QS4 for the surrounds. Already have an Energy Center that I am planning on keeping for awhile. The M60's will be roughly 8' apart on either side of TV, and QS4s will be on walls about 6' up.
Based on wife "feedback", the sub needs to be in the rear of the room. Currently I have an old 8" down-firing JBL that came in a $399 5.1 kit from BB. I would like to upgrade the sub, but am on a budget and don't know a lot about subs. I want to keep the single line in from the Receiver (Onkyo 606), and will be running sub-cable through ceiling and terminating in a wall plate. The budget is from $300 to $500 US.