go to supergrit.com you can get the pads for $2.75 a piece and shipping is only $8 for as many as you want. I bought the 360,500,1000,2000,4000 out the door for 21.75 shipped. I have looked and that is the cheapest place you can get them anywhere.
From my experiences mine last a good while, I think it is hard to tell when they are getting worn out, if anything they are just a higher grit than what you started out with, which I think is cool becuase, you can use a semi worn out 2000 pad and get something around 3000 grit, thats my theory. But if I were to give you a random answer I would say about 15 balls, I have heard from Jeff Ussery that he uses his for like 30-40 balls before he thinks they are to worn out, and not doing the job he wants. I am still using the same pads I bought like 3 months ago, and I am always tweaking my covers.peace
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I thought my Hammers hit hard, until I whipped a LM/L ball into the pocket. WOW!
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