I love bashing these special shafts. It's like people just want the easy way out and dont want to learn how to play with thier regular playing shaft.
I've owned 2 of the old block letter Meucci Originals, and the only one that had a whippy shaft, was one that had a 12mm shaft. And even that one I could use to play with.
I've also owned a Schon, 2- Espiritu's, a 5280, a Viking, and several custom cues. Not once have I even thought about putting a X-shaft,314,Z shaft, or whatever shaft on them.
I learned to adapt to how the cue played.
I like to put it this way. Why would I spend 400$ to several thousand dollars, on a custom cue, and then turn around and put a predator shaft on the cue?
I would hope that Gilbert, Bludworth, Scruggs, Espiritu, JossWest, SouthWest, Kikel, Coker, BlackBoar, Josey, and many other custom cue makers, know a thing or two about making a damn good playing shaft for thier cues.