Pick an extremely strong password that is unique to the safe alone, and don't write it anywhere, don't tell it to anyone. The chance that it will be hacked is essentially zero if your password is reasonably strong, and the additional security you'll gain by not having any passwords shared across accounts, and none written or saved anywhere else will far outweigh that small risk. Hackers, like most thieves, look for the easy targets. With a decent password safe you are not an easy target.
I don't know how I've worked with computers all these years without one of these password apps, whatever they are.