If you go to
Custom Golf Clubs & Equipment by HorsePower Golf & Pat Dempsey Web Cam Watch Us Build Clubs, and then to the shafts section, you'll see that HP Golf is an authorized tour shop for UST. Near the top of the shafts page, the tour shafts are listed.
IMO, those shafts aren't for many people here. They're all built stiffer and with firmer tips than an average golfer would benefit from in a shaft.
Other than that, the only thing I've heard of is weight and spine sorting/matching. Are you really going to tell if your 5-iron shaft weighed 3 grams more than your 6-iron shaft at raw length? Probably not in a million years.