Distributor question

Never in 20 years have i had a plastic one break.
but i've always used a new one.
ever since i was told to get that junk out of there (it had a brass one when i purchased it)

you might use a steel gear with a roller cam i can never remember the appropriate material for that kind of cam material but gears and pushrods and drives seem to be updated when a roller cam is used

you could use the brass gear with a standard cam they do tend to knife edge the teeth rather quickly and make your oil sparkle. its harder but in materials terms not as tough.
use in a motor that gets stripped and checked regularly. They won't break but they are a sacrificial part that wears in a way that the nylon one doesn't seem to.

the nylon copes well with a slight mismatch of pitch between your aftermarket cam and gear
the metal ones do not cope as well

the main reason for nylon was to protect the bushes in the dizzy from harmonic vibration in the cam.

steel shaft in olite "like" bushings don't like repetitive shock loads and a long cam with harmonic vibration would provide just that

less so on a slant 6 than a hemi 6, due to the thickness of the cam stock between the lobes being greater on the slant, and the drive is at one end, but it is a six. i.e quite a long cam

Just my view but upgrades are either better or necessary changes.
i have not done anything that has made it necessary to change to steel or iron gear.
and a yellow metal gear seems to have drawbacks.

Dave