I offer the following photos regarding past discussions of using plastic/Teflon bushings in wood works clocks. I am not certain we can draw many conclusions, other than Teflon suffers from the same wear as other bushing materials, at some rate, perhaps less than some other materials. This example is particularly of concern as the shaft is .100" stainless steel, and there is a great amount of wear as can be seen on both ends of the shaft. The Teflon (not certain as to the composition of the bushing, spec sheet does not call out the material) bushing is an insert in a plastic housing. This amount of wear occurred in approximately 4380 hrs of operation, not a clockworks device, but running under a very light load. Total revolutions of approximately 75,000,000 in an uncontrolled TX environment, which certainly includes some very abrasive dust. However, that would equate to nearly 150 years of a clock running with the bushing located in the escape wheel location….so, while wear occurs in plastic bushings its rate may preclude any major concern to us when used in WW clocks lower in the train…… my conclusion, if we use proper plastic bushings wear should not be an issue in our lifetimes…..I still prefer wood, brass, or bone bushings, depending on what was in the clock originally, but a proper material plastic bushing should last a very long time.