Jeff, I have been building enigines since I was 15 and have always used HV pumps in the engines I build and have never had a gear drive failure. At my current age that is a lot of engines. I am not sure why any of the ones you have seen failed. I have several customers with over 100,000 on there engines and they are still going strong. We use them on Dodge, Chevy, and Fords and I would never use anything else. The safty margine they provide is well worth the extra cost to me to be sure that when my customer kicks the rpms up the
oil will still be there.