SyncThing vs Synology Drive
I'm impressed with SyncThing. It's far more flexible and versatile than the Synology Drive application.
Maybe it's a bit slower, but that's only seconds, not minutes.
Setting up Synology is a bit more intuitive, but once you figured out SyncThing, it's at least as quick to add a new folder / sync, and ST doesn't complain if you want to sync 2 subfolders from a specific folder.