Dizzy,
All the info says the surface is 600 grit. Believe me it acts like it.
AGain, I guarantee it's stronger than PK 17. I can't tell you the nitty gritty details, if needs be. I suspect it is stronger than PK 18, but smoother like PK 17. (PK 18 is flippy.)
You can put any finish on it that you like. Sanding: 8000, 1000, 1500, 2000 etc. And any level of polishing.
Aince RG diff is relatively low, keep the pin-PAP distance 5" or less and 3" or more. 4" - 4.5" is good. Mine is at 5" but under the center of the bridge,
This ball is MONEY!
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"None are so blind as those who will not see."