Biggest mistake people make is not taking these balls back to factory oob after the oil extraction. In your case, a 600 grit ball with polish, will not react exactly like a 4000 grit ball with polish(factory oob for TNV). It will be a little earlier with not as much backend as it was brand new which you seem to like. Due the hot water bath every 50 games or so and that ball will run for awhile. Just remember to take the coverstock back to where you had it.
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