The Silver Diamond's coverstock is Brunswick's PowerKoil 18. It has proven, since it first came out in 1997, to be almost indestructible. Keep it relatively clean, resurface it when its track begins to make the ball hook too early, and my best guess is 800 - 1000 games. Absolutely tons of people are still using their original Danger Zone in my neck of the woods.
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"Just because you can do something does not mean you should do it."