Which sub is better for audio


I am looking to buy a sub to be used primarily for audio. My options are Sunfire true sub, HSU, and Bag End. I intend to spend no more than $1500. Your advice will be appreciated.
planckscale3555
I bought the Genesis 928 and am very happy with its 2 15" woofers. Great Stereophile review. It also has an accelerometer mounted on it to prevent bass overhang.
Talon Roc, Hands down, this is the best sub you can buy. Put up against the RE1 and never bottomed out.
I am using a Sunfire Signature subwoofer with my Magnepan 3.5/R.You can get spectacular results if this sub is moved away from room boundaries (certainly not in a corner as recommended by Bob Carver) and if the volume is kept at a sufficiently low level so that the sub is audible only with bass material below about 50 Hz (if x-over is set at 30 Hz) and with the proper use of the phase adjustment . My Signature disappears completely in my system. The blend is seamless and the result is very musical. I tried the RELs, but they were too difficult to set up because the Phase adjustment was only 0/180, whereas the phase of the Sunfire can be adjusted continuously from 0 to 180. In the case of the RELs you had to move them until the "correct' location is determined. I think the Sunfire Signatures have received a bad rap from users who have not set them up properly. I get clean extension to about 16 Hz with air, power and definition.
So far I am leaning towards The Vandersteen 2wq or the Rel Strata III, that is, if I find them on sale. Gmorris, your comment on the phase adjacent on the sunfire is interesting. I am still listening... Thanx