UST V2 is definitely more tip-stiff shaft. With my shitty swing I can get the face to close in time, but I had some decent golfers hit it - and they were smoking it. I think the combo of TP clubhead (square) and tip-stiff shaft requires a bit higher swingspeed than mine? Duno, all I know the same clubhead with the aldila prototype (in TP colors) works great for me, this one doesn't