I think the Rival is the best all around ball on the market. I could use this ball on just about any condition except the extremes of Heavy oil and Burnt lane conditions. When I polished it, the ball was cleaner through the fronts and was still smooth at the breakpoint. As for the Momentum, I have seen Chris use this balls several times, and it is a good ball too. Strong arcing pearl reactive coverstock. I would say that it would depend on what conditions you run into more. If you bowl on conditions with oil in the heads, I would go with the Rival, if you bowl with Drier Fronts, I would go with the Momentum.
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Thanks
Bill
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