I've played the QST for a few rounds now, so I have a decent feel for them. I played a Z Star for a couple holes (before it decided to go scuba diving), and to me there was a very noticeable difference in feel. Again, I notice the biggest difference between balls off the driver or putter, and the Z Star felt (and sounded) harder off both. I didn't keep it in play long enough to notice much more than that in terms of performance.Basically a phrase i use daily in my job...
Sooo here is my dilemma... I usually play QST, but have noticed a bit better perf (perceived) on spin with z star and distance on xv as well as VFIT for RXS multiple times.
This is where it becomes tough to feel a difference