Plastics Comparison: UHMW vs MDS Nylon
I also ran a test on Delrin (acetal) for 15,500 cycles. The weight was also increased as I thought that the contact area was larger, though this was incorrect, as the last photo shows. Dimensions were essentially unchanged, within half a thousandth of the starting value. Very slight squeak/creak sound later in the testing but definitely a good choice if looking for performance between nylon and UHMW.