I previously ran 150,000 AMD gpus in all conditions at 100% utilization for years. I currently have a multi-million $ cluster of enterprise AMD GPUs.

A couple real world points:

1. They generally don't just fail. More likely a repairable component on a board fails and you can send it out to be repaired.

2. For my current stuff, I have a 3 year pro support contract that can be extended. Anything happens, Dell goes and fixes it. We also haven't had someone in our cage at the DC in over 6 months now.