I've thrown mine a ton, felt like I was losing a little on it, so I sanded it down with a scot brite, put it in the bath tub, then took it back to the shop and had it taken back to 4000 and it worked like it did the first night I had it. In fact first game after the resurface was 289 with the back 10.
I even bought mine NIB off of eBay and it's been the best ball I have ever thrown.
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Ahhh Disco Biscuits!