I've never used them, but I do use poles for hunting pheasants on snowshoes and skiing of course.
What does a set of these poles have going for themselves that a good ski pole doesn't?
I'd say adjustability. Going steep downhill you can lengthen the trekkking poles and likewise shorten going uphill. Though not ideal, I believe ski poles are usable. I'd choose them over a stick.
Another plus to a pole over a stick is the wrist strap. It can be used as additional weight bearing support and when glassing the straps allow the pole to simply hang from the wrists. No need to lean your stick against a tree or your leg.
