Nylon Harness with leather or Beta wear parts?

Today I went to Locust Lane Harness shop in Romulus, NY to order a D ring Harness for my Donkey. I am hoping that I can get a harness that I like so much that I will have them replace all my harness over the next couple years. I ordered a nylon harness with wear patches (britchen, back saddle, etc.) I am leaning toward the beta patch, but don’t want it to crack or break down faster than leather would. In either case I will hang the harness in the barn and never clean it, so the beta seamed like a good bet. Is beta the same as “granite”? I think it is. I also told them how long to make the front tug (18″), and the rear tug. He will need to hook up with the big horses so a long rear tug will make them match. I checked the D rings and front hooks to make sure they were the best kind. Everything seemed to be in order. Dad wasn’t home so he will call me with a price and ask about the leather patches.

Let me know if anyone has found one to be way better than the other when sewn on nylon.