i ended up liking the sealed acoustic visions mrs-10 sub over the hsu.
the hsu actually had some impressive slam and overall i liked it, but i think that for my music tastes.
ghm was right, it sounded like it was a bit slow, a bit behind the speakers with its timing.
no matter what i tried i could not get hsu sub to disappear like the mrs-10.
i was always aware when the hsu was in the system, and the mrs-10 was more cohesive and less sloppy, and let me listen to the music, instead of drawing my attention to the fact that there was a sub in my system.
i almost kept the hsu, thinking i could move it over for home theater duty, but i dont have a home theater yet. so my wife, in her infinite wisdom, said, "keep the sealed one, send the HSU back, and buy *another* sub when we get the HT hooked up."
i knew she was a keeper.
thanks to everyone for their feedback.
brian