I'm pretty sure it's password encrypted, so in theory yeah it should be secure if your master password is, but if someone gets access to it I think they could try to brute force your vault open.

It's not that hard to maintain tbh, it's actually simpler than a lot of other self hosted options because it just works on every device with no weird setup with syncthing. It's made my life so much simpler and I like being able to quickly share logins with my fiance.