Oddly enough, they were the bike that buell produced because Harley made them, as I remember it they made a loss on every single 1 built, yet they were the longest running and biggest sellers, can't remember the a teal sales figures but can look them up if anyone's interested.
There's a waiting list for them on the uk buell forum, as they were never officially sold here, some people just privately brought them over. Is (afaik) basically the same engine as the twin used in the xb range but without the rear cylinder, basically half an engine.
*waits to be corrected*