FoxyMulder, Thank you so much for everything so far.. You have been a tremendous help. right now on the conservative side I am leaning toward the PB-1000 it is about $250 less than the cylindrical SVS and about $200 less than the HSU. I will continue to do my research and look at everything that this thread has brought to light. I really am looking for the best bang for the buck on a budget ($500-$700) but would definitely rather stay more toward the lower part of the budget ;-)
Consider the long term benefits of the HSU, for $200 more you get a more powerful subwoofer and a great warranty to boot, its worth stretching that extra $200 i think, sure the PB-1000 will be fine but the HSU has better bass extension at higher volume levels and i think its worth going for over the PB-1000.