This thing is really, really good.
However, as I've discussed the golfers whose swing is more pivot oriented, they can pretty much play with any type of shaft whereas the golfers who tend to throw their arms at the ball (even with some pivot), they tend to need a more specific type of shaft.
Also, 'snap releases' tend to need heavier and stiffer shafts (their hand speed usually needs to be slower, per Homer Kelley's Endless Belt Concept 2-K), and more full sweep releases need more flex and lighter shafts becasue their hands have to move faster to generate clubhead speed.
I'll be interested in what mine says as I get close to finishing ABS. I do prefer heavier shafts because I think it makes it easier to get in the proper downswing sequence.