I dont know anything about the HSU subs, but the SVS i do know
The SVS PB-10NSD is a great sub at less than $500.
I thought the paradigm PW-2200 was much more than $550, not unless this is an older version. The current PW-2200 has a 500W RMS/ 1500 W peak amp. I think u might have been looking at a previous version.
If $550 is for a used Paradigm then i would rather have a brand new SVS PB-10NSD.
But when comparing the two new, i would lean towards the Paradigm PW-2200. Bigger amp, wood cabinet vs vinyl, 12 inch vs 10 inch, deeper extention, heavier sub too.