I've been using Syncthing for some months now and it's working well for my use case of keeping laptop/desktop and home server files in sync. I had one occasion when I lost everything as I'd brought up syncthing on my server without the "sync" directory mounted. It happily deleted all files from my synced laptop as a result. That's now fixed, but it was a buttock clenching moment. Yay backups, and a third machine (desktop) which was suspended and thus out of sync, so still had my data.

Upstream developer is very friendly and attentive & seems happy to discuss new features and use cases.