the pearls(swarm, street rod, psycho), in general, will be longer, handle less oil, and flip harder in the back. the solids(copperhead,rival) will be earlier, handle more oil, and be smoother.
if i had to take anyone of these to be my only ball, i would either get the rival, or get the copperhead(most likely with a weaker drill or polish.)
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Angle and vector be damned, we're going to the moon!!!