For heavier volumes of oil, I'd go with the Pin Slasher. Yes, the cores are identical in the two balls, but the coverstocks are different. The GB 12.7 used on the Pin Slasher is a good deal more aggressive than the Playmaker's GB 10.7. Also, the Pin Slasher is a solid, whereas the Playmaker is pearlized. Because of this, the Pin Slasher will generate more traction through the heads and a more aggressive midlane read, with a smoother and earlier reaction than the Playmaker. This reaction will match up much better on slicker lanes than the Playmaker's, which will be cleaner through the heads with a sharper backend, even with a surface change. If you were to put the two balls at identical surfaces, the Pin Slasher will easily generate more traction than the Playmaker. GB 12.7 is a pretty aggressive cover it was used on the Infinite One, which i own and love.
I hope this helps you. Good luck!
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to the pits!