Business was VERY good for me this year, so I'm gonna finally get an SVS to see what I've been missing. I've heard very good things about HSU subs as well, but as far as brand recognition goes, my mind seems to connect more w/ SVS. Anyway, my room dimensions are easy: Imagine a small to medium size rectangle room that measures 25 ft. long, 11 ft. wide, and 8 ft. high ceilings. I currently use a Sony SAWM40 subwoofer that does just OK, but seems to leave alot to be desired. My receiver is a 7-channel Panasonic Digital amp. Based on my setup and room size, which sub would be best matched to my room? Even though my Sony sub has a 12 inch woofer, I get the impression that a SVS PB10-NSD sub would best it. Is this true? From there, I was also wondering what a 25-31PCi, 20-39PCi, or PB12-NSD would do for me since all (including the PB10-NSD) are $599 and under. If the PB10-NSD would be a significant upgrade, I'd love to go that route and save a little cash, but I did set a limit at $599, so no big whoop. My listening habits are a movie or 2 every month, but if the sub is as good as I expect, that may change. Anyway, what do you recommend? Thanks.