Doug,
I have had a Pro Purple for a long time. While it is not of major use for me, since I prefer balls specific to an oil condition, it is probably the most versatile ball in my assortment. Mine is drilled approx 4.5 x 5, with a 2" pin-to-Cg distance. It covers for me, if necessary, what your Chery Bomb, Blue berry and Inferno *probably* (by my best guess) covers for you. For me, it is a medium to medium heavy oil ball, with the stock coverstock finish. If I am lost, and the oil is more than medium-light, I can always find a way to the pocket with it. Its hitting power is not tremendous, but more than average.
For your purposes, I am not sure exactly where you can best use it. By dint of your specs (speed and rev rate), I'd guess it would fit somewhere above the Cherry bomb and in the range of the Blueberry with less length and less backend (but still plenty of hit). If your rev rate is average for all bowlers, I'd put the pin in the 3.5 - 4" pin to PAP range (remember this ball has very little flare; its cover is its strength.) and CG in the 4" range. Stacked is fine with this ball as it's almost impossible to make it flippy. I'd guess this would be the most versatile for you: 4x4, 4x3.5, 3.5x4, in that neighborhood.
RG min to max: 2.53 - 2.56 (medium low to medium)
RG Diff: .028 (3-4" flare)
Oh, the cover is probably Brunswick's DTX-1 or 2 and is definitely version 2.0.
This cover lasts freaking forever, absorbs almost no oil; you can't beat it with a stick.
I have used it with slightly slower speeds on true heavy oil and have been amazed. It is meant for mediums.
Good luck and thanks for all the fish.
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