Don't dismiss the Hsu quite so quickly. My suggestion would be to make your choice based upon price and perhaps, potential. One VTF-3 is more than adequate for my 4800 cu.ft. room. I now have two, which is prominent overkill....(but the headroom...oooh). Add in the possibility of attaching a turbo kit to one or both and I could have half the town knock-knock-knocking on my door.
I don't wish to start the which-is-better argument all over again. Hsu and SVS both make fine subs that will do a great job for you. Price should drive your decision, IMHO.