Well Syncthing requires some set-up, but it’s pretty simple. Basically, you just need to make sure that it constantly runs on all devices, but there are plenty of guides online that help you set up auto-execute. Dropbox works just fine, and since your KeePass database is encrypted, it’s not a big deal. I’m just the kind of person that likes layers of security, even though it’s probably overkill 🤣