It's great that many HNers like Syncthing, but personally, I seriously tried it maybe two years ago and didn't have a great experience.

I wanted to sync my personal files between three computers, two desktops and a notebook, which don't always see each other. At first, this worked great. Obviously, there were conflicts when I accidentally edited something in two places without syncing up. What I didn't figure out was how to permanently resolve those. I ran into endless cycles were I had a conflict between two systems, resolved that, but the third one hadn't seen the conflict resolution, which produced another conflict, which I resolved, which the first system hadn't seen yet, ad infinitum. At least, that's what it looked like. Among other errors, files long since deleted on all systems would still show up as conflicts.

To be fair, I didn't actually lose any data, and it's very possible I did something wrong that would be obvious to other people. But to me, it wasn't at all clear what and why, which scared me enough to move away from this setup. I don't want to take a lot of chances with my data.