I thought everything was fine until

there is an old adage
"succesful testing does not prove the abscence of faults, it proves the abscence of known faults"

and THIS is the very reason not to go outside the datsheet, you can test till the cows come home, but you will never know that there is no problem.

I recall a series of units tht ran flawlessly for years untill the new ones started experiencing the feared "it fails once a week". It turned out thet the hardware 'designer' had 'designed' to typical values and when the next batch of chips were in another correct place between min and max, the above happened.

Erik