BTSync is very good, I've used it extensively (see http://blog.bittorrent.com/2014/06/24/sync-hacks-waking-up-some-very-old-instruments/ ). Now using a 1.3 version but leaving BTSync at the end of the academic year. The limitation to 10 folders in academic projects with diverse teams and students makes it unusable for similar purposes. It's really bad to see die such a good piece of software because, from my point of view, an unfortunate commercial decision. Exactly the opposite that often less can be more... Very sorry to leave BTSync.