Have you gone to the ebonite website and compared stats? You can't always judge a ball by it's stats or by what a company has to say about it, but it will give you a general idea. Basically, the Mass Bias is significantly higher in The One it has 5 points more reaction is advertised to handle heavy oil (though some would argue it needs to be taken down from it's 4000 polish to make that true. It carries further through the oil with a more powerful backend reaction. The Over Time on the other hand is designed to react sooner with a smoother break point angle. That's just my interpretation though, I've only been learning for about a week myself.
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Look for me in the upcoming PBA Tour! I'll be the guy in the back row with the foam finger singing "Take Me Out To The Ball Game" during the 7th inning.