Everything that would wear out is replaceable, and most of it easy and/or cheap to replace.
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Quoted from isJ:No. Make sure the balls are in good shape and wipe it with a microfiber cloth to get rid of dirt if it start accumulating.
What he/she said, too. Accumulating dirt makes things worse, wipe it down with Novus 1 or Wizards Mist-n-Shine every 100 games or so.