I have used one of these pads for years and it has yet to show any signs of wear. Heck, it doesn't even look used! The material that the Pad is made of is truly self-healing, and I think you can count on it lasting a lifetime. Mouse pads are a popular substitute, but they are thinner and softer, and don't work as well as this Perforating Pad.
Tip: To make your tool glide through the paper, put a piece of waxed paper on top of the pad. The tool will be waxed every time you pierce the paper.