Couple of things to mention to help with distributor gear life:
1. Gear material must match cam material.
2. Gear must be installed to spec on shaft. There is a Ford spec, and there is an MSD spec and it depends on if the thrust clearance is taken out of the gear before measuring on which one you use. If this spec is not held when installing a new gear, you will have wear.
3. You absolutely can not just put a new gear back in the same spot so that the pin holes line up and call it good. Different gears will have different dowel pin holes. You have to measure each and every time and if necessary, drill another hole.
I don't have distributor wear issues, even with a high volume/high pressure
oil pump and whatever bearing clearances I'm running at the time.