I don't have the Neptune, but I do have the Venus. Mine is drilled pin next to ring finger, 4" from PAP with the CG swung towards grip center, no weighthole. In OOB condition, the ball was too strong for light oil. I have taken the surface to 4000 Abralon and added a coat of Beans' Secret Sauce. I bowl on a 38 ft THS, buffed to 40 ft. In my estimation, it is medium-light oil. My ball speed is 16.5 mph off the hand with a rev rate of 325 rpm. The Venus, with this layout and surface prep, allows me to play the track area. I have had my highest series of the year with this ball.
I would not classify the Venus as a light oil ball. Depending on the layout and surface prep, it could easily handle medium oil down to medium-light. Because of the low differential core, unless you have a lot of hand, the Venus isn't made to cross lots of boards. It just doesn't have the motor to do that. No knock on the ball at all, as it is one of my favorite releases from Roto-Grip.
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Hook 'em Horns!
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