No experience other than the nylon stems that come on cobs. It's a very soft material, soft enough to actually make me want to chew it. I'm sure there's a harder grade though, one designed for machining instead of injection molding.
I've experienced nylon stems on a number of manufactured pipes, usually very low end lines. It's lousy to work with, much worse than ABS. Removing tooth marks is a right bugger.
Regards,
Frank.
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