aviate, navigate,communicate?
Go and read the ATSB report on the Mojave Air ambulance accident at Bankstown. That pilot was heavily criticized for not making a mayday call. I guess you just cant win.
If I had a low level incident that had me worried, I'd be thinking about getting the services out early, which would prompt you to make a mayday call. Plus, the Mojave incident has burned in my mind that you need to make the mayday call to prevent AsA & ATSB from attacking you later.