Pin-ins offer a smoother, less skid/snap reaction. They are best suited for arcing drillings with an early breakpoint, because the ball will not break as hard as a pin-out because the mass bias of the core is weaker (yes, even symmetric cores have an MB, even though the effect is not as exploitable as in a asymmetric core with a PSA). Heavy oil balls are well suited for pin-in configurations, withn a drilling of the pin below the fingers.
Personally I can tell that having a pin-in or pin-out makes a big difference in ball reaction. Me and a friend both have Traumas, mine is a pin-in with the pin at 4:00 from ring finger, my friend has a 3 1/2" pin out with the pin at about 2:00 of his ring finger. Both balls could not be different. My friend's Trauma is a jerky beast with a wickedly flipping backend, mine is a great control ball with a steady, arcing move. Both cover the same amount of boards, but they break MUCH differently.
Therefore I'd suggest cheking pin-to-CG distance before you buy a ball, because it will basically determine how the ball will react and which kind of drilling can be applied.
Also, take a look at Brunswick's drilling sheets and the drilling patterns: they all show suggested pin distances for the different drillings, and I can just say that it is something to mind if you want a proper ball reaction. You will not get a pin-in to become a long-going flip monster.
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DizzyFugu --- Reporting from Germany
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