Hi- I just bought and set up Polk RM 6200 surround speakers and the PWS 350 subwoofer (the 10", not the smaller 250).
Great sound! As it happens, I also bought an A/V receiver that offers a 6th channel for center rear, and it came with a free speaker for that channel. I haven't set it up because my couch is against the back wall and I can't put the speaker behind my head. Is there an alternate location I could put the center rear channel? Does it make sense to mount it at the top of the wall, hanging from a bracket on the ceiling, and face it straight down onto the heads of listeners sitting on the couch?