There was some concern about the security of the product: http://2014.hackitoerg...

		rpedroso on May 12, 2015 \| parent \| context \| favorite \| on: BitTorrent Bleep Now Publicly Available Across All... There was some concern about the security of the product: http://2014.hackitoergosum.org/bittorrentsync-security-priva... These concerns were amplified by the difficulty of auditing a closed-source product. Their argument that hashes are one-time secrets and not permanent keys is difficult to validate without access to the source.

I personally switched to Syncthing (and the Syncthing-GTK GUI) and never looked back.