But are you sure the temperatures are constant even when the bowling alley is closed? Does the locker share an outside wall? I've only had one ball crack, and that ball sat on my back porch (completely enclosed, not your typical "porch") but it sat against an outside wall and I'm almost positive those temp changes are what caused the cracking. I have a Heat remake, has a fair amount of games on it, haven't had any cracking issues.
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What are you gonna do? Beat me with your Jesus stick?