Pin axis is the ultimate ROLLY layout. The core is in its stable end position when the ball leaves the hand, it is DEAD. Can be a choice for outside lines, but I found axis drillings tricky. While such a ball does not overreact at all and blends out wet/dry conditions, the early roll depltes energy easily, and as the pooh mentioned, carry and angle can be issues. Better play fast and firm with such a thing, otherwise I'd expect it to make a good spare ball.
I'd also rather vote for a half-axis setup, with the pin at abot 2" from PAP. This is still a rolly thing that IMHO needs a fast and firm release, but has some arcing move on the back end.
I have a Power Groove Particle Black Sparkle with such a setup - a pretty special piece, moves and plays very different from any pin-above-leverage-point ball I have. But it feels at home straight down between 1st and 2nd arrow.
Check my review of it, and here's a video of it, showing how it arcs:
http://de.video.yahoo.com/watch/5346519/14091083--------------------
DizzyFugu - Reporting from Germany
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