We used Resilio Sync (aka Bittorrent Sync aka BT Sync) for a while for the Tron project ( https://reddit.com/r/TronScript ). It worked great for our use-case: distributing a large number of files to a large number of nodes who required read-only access. Anytime I changed a file on the master node it would blast out to everyone else while simultaneously preventing any other node in the swarm from propagating changes.
Unfortunately with all the restrictions they introduced, it stopped working reliably. Internally they introduced a hard-coded peer cap of something like 32, while our swarm was already over 500.
We switched to Syncthing and it's been working well. There is still one major issue and that's that anyone can mark their copy of the folder as "read-only" (formerly called "Master"), and then they will attempt to propagate changes out to the rest of the swarm. So, there's that. But strictly on a distributed file syncing level, it works great.