I can't speak for the Predator Z, but I bought an OB-1 shaft recently. The OB-1 offers similar performance advantages to those of the Z.
At first the OB-1 was a revelation. I was astounded how much it reduced deflection. However, the fact is, for me, a low squirt (deflection) shaft was not the answer.
I've been playing pool for 40 years and and to relearn the myriad compensations necessary when shifting to a low squirt shaft proved more bothersome than helpful. Moreover, the dull feeling of the OB-1, as compared to my stiff taper Southwest, convinced me to put the OB-1 away.
In short, it may be easier for someone whose habits are less ingrained than mine, to pick up a shaft with dramatically different performance, but it was not for me. I guess the bottom line is, like most things, you need to try it for yourself. There is no magic bullet that is right for all.