Hopefully this comment will be of use to someone. My stack is Syncthing and Backblaze. It works very well for many terabytes of data. No huge issues yet, altho

Hopefully this comment will be of use to someone. My stack is Syncthing and Backblaze. It works very well for many terabytes of data. No huge issues yet, although sometimes Syncthing gets into a weird state about what's been synchronised for a while. Generally a restart of the daemon will fix it. Backblaze used of course in case all my devices storing synch'd files all fail before I get replacements in place.