I've always been in favor of protecting the system. With manual resets it may cause emergency calls but it eliminates most of the ( well its been acting up for 2 weeks ) calls that auto resets gives you and I don't mind the ot.
It seems in my case the previous techs and owner just ignored the problem becasue of the automatic switch. I even had the relief valve blow because one of the switches failed from too much cycling. After installing a manual switch it put the owners feet to the fire. It looks like their gonna fit in a new condenser in the next budget.
I prefer manual reset myself. If it trips...that means it tripped for a reason and the problem needs to be addressed to prevent anymore potential damage to the system.
It helps us techs cover our a**. There has been many times in my experience where the client is aware the system isn't working properly, but still working intermittently and short cycling, and they'll wait a week to call in for service because they think it will magically fix itself. I've seen it too many times. And it's usually at 3 o'clock on a Friday when they call in and they need it fixed now!!!
Auto reset is okay for trouble shooting or used temporarily while the real issue is addressed. But when the job is done and I walk away, I make sure it's set for manual.