The Sure Fire is already a stronger pearl reactive ball. If you want a good addition, and this is your only ball at the moment, then I'd suggest:
a) a spare ball - any polyester ball will do, and they are cheap, for those pesky corner pins
b) a lower RG solid reactive or particle ball, with a higher RG differential (0.04" up) and without a polished surface that will, with the proper setup, handle more and longer oil, roll earlier and have a smoother reaction shape overall.
For the latter, I'd suggest a look at Storm's Agent line, the Special or Secret Agent if you want to stay with this company. But other companies have similar offerings
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