What a great opportunity to try the HSU and A/B it with your current sub!
They make a great product and my choice was between them and SVS (I got an SVS). I had a Velo CHT-10 for a couple of days and had to return it. No matter where I put it, the room just swallowed it up. No problem now; the 20-39 PCi is burly.

I'm guessing we will see a post pretty soon describing the acquisition of a brand new HSU!