Hsu Research Subs w/ Electrostats

Has anyone had any experience with the Hsu research subs. I want to add more bass to my system ,I am very happy with the detail of my speakers and different cables tend to add more bass but lose detail. The Hsu design looks interesting to me(similar to the Pipedreams). Any experience or thoughts would be appreciated.
The Magnepan Users Group at audioasylum.com has discussed the Hsu sub at length and is worth a look. Briefly, it is usually highly rated and supposed to be a good company to deal with. Also, qaudio.com has a demo for $50 off retail. Good luck!
I use an Hsu sub (the 10" cube model) with a pair of Quad 57 esl's in a home theater setup. As long as the crossover point is kept pretty low, say 50-60 Hz, I think its great! Bill