Make sure you run a collar on the distributor shaft with the correct amount of clearance. The collar keeps the gear from climbing up and down on the cam gear, which significantly increases wear. Without the collar on there, the clearance is only limited by how the clearance between the distributor drive tang and the slot it fits into on the intermediate shaft. That's usually quite a bit more than is optimal.
You can see how much wear is taking place by pulling the distributor and carefully looking at the thickness of the gear teeth. I checked mine at each oil change. Don't run excessively thick oil either, 10-30w should be fine for most climates.
I've also wondered if cryogenically treating the gear would reduce wear.
When I changed cams, I went with the treated steel gear from Crane or Crower. I forget which one, but got it from Hughes.