IMHO, these balls are good for the same condtion OOB, but achieve their performance in different ways.
SZ is rather rolly and revs up quickly. IMO not a flip ball, but skids more easily through the heads and reacts stronger to friction, delivering the core's energy quicker. IMHO good when you have a higher ball speed.
The Rattler has more back end and IMO reacts with its Activator shell less spontaneous to friction, should overall deliver a "sharper" look on the lane.
IMO I'd decide between them, not put both in the bag.
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DizzyFugu - Reporting from Germany
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