Personally I don't use a removeable thumb slug, and the 19 bowling balls I currently own feel exactly the same. Each has one piece of white tape because I like the way it feels, and I can call my ball driller, order a ball, tell him the layout that I want, and throw it with no adjustments at all. He is now the 4th driller that I have used exclusively over the past 15 years, and every one of them could do the same. When I first moved to Vegas, I used a driller in California who I would call to place an order and he would ship the ball to me drilled perfectly. Again, if your driller can't duplicate your drilling exactly, it's time to find a new driller.
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