I am trying to decide which would be a better rear center channel speaker. I have a Denon 1804 receiver,qs4 surrounds,vp 100 front center and am getting m22 for the front mains very soon. I can't decide if the rear center should be directional like the vp 100 or more dispersial like the qs4's. And if it is directional would the vp 100 be a good choice? The room is small 12x16, carpeted and the listening positions are varied. and yes I am running a sub. any thoughts?

I am pretty sure that if you are running one rear speaker it should not be directional. Sounds coming from directly behind you can in fact sound as if they are in front of you.

In your case I would suggest a QS4.