Game,
I've owned four Visionary balls up to this point, 2 Granite Gargoyles,1 Green Pearl Gargoyle and 1 Purple Ice Executioner, and I have never noticed a drop off in reaction. Since you're particularly interested in partical equipment, I'll only talk of the Granites and the Executioner. For me, the coverstocks of both of these balls have held up extremely well. The Granite is very easily dirtied up and tracked, but cleaning easily removes the dirt and grime and keeps the ball reacting strong. The Purple Ice is very much the same. The ball, in box finish, will shine up over time, but it is easily taken back down to box finish and it has maintained crisp reaction. If you're really concerned, treat the ball with Doc's Elixir, as this will keep oil from soaking in and should give you an extra measure of protection. In my opinion, Visionary's partical technology is better than any that I've come across, and I've tried several. Their balls are durable, easily tweaked, hard hitting and very user-friendly. Even if you decide to go with another choice for your heavy oil needs, I'd still recommend looking into giving some Visionary gear a chance. I've never come across anyone who has tried them being disappointed. Hope this helps a little.
Gene J. Kanak
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Bowling is without a doubt the dumbest, most pointless, most idiotic excuse for a game that has ever been invented. So, what time are we bowling tomorrow?