My Syncthing experience matches Oxodao's. Over years with >10k files / 100 gb, I've only ever had conflicts when I actually made conflicting simultaneous changes.

I use it on my phone (configured to only sync on WiFi), laptop (connected 99% of the time), and server (up 100% of the time).

The always-up server/laptop as a "master node" are probably key.

That is good advice from both of you. I knew it has to be me because it's honestly one of the most successful and popular open source tools I've worked with. I think I should've made that more clear in my original comment.