I'm setting up my surround tonight and need to decide on some speakers. Currently I have a polk center channel w/ 2 drivers, 2 polks in front & 2 jbls in the rear (someday I'll get rear polks). Regarding the rear center channel: Should I duplicate the front center polk, or wait until there is compelling software? I don't know if I have any titles that would utilize the 6.1 capabilities of my receiver/speakers. Regarding the subwoofer, I can get a 10" Velodyne powerred sub for $279 open box. My other choices would be a sealed 10" Velodyne for $399, or an 8" for $299. Also I could get a 10" Polk for $349 or an 8" Polk for $249. I was a bit surprised about the cost of subwoofers in general - simply because I'm new at this, so any recommendations regarding cost and performance would be appreciated. The salesman seemed to recommend the Velodyne even though my other speakers are Polk, but I think HTF has more experts than they do.. Let me know Thanks! Also - should I pick up an optical cable to run from my DVD to my receiver? What should I look at spending on that?