BTSync has so far been a great product and aside from one particularly bad experience, has been doing wonders to keep my computers synced. The exception happened about a week ago. I have several machines that have several folders synced as a backup system. (I lost years worth of work and my entire music collection earlier this year when my main machine and NAS drives failed within a week of each other so I'm a bit paranoid now.) Even though everything is synced, I tend to do different workflows on different machines - graphics and video work on one, development on another, etc. So for each synced directory, the data flow tends to be unidirectional for the most part. I had one machine switched off for about a month while i dealt with some power supply issues with it. When I powered it back up and wnet to work on something else, it immediately started syncing old files to my development machine, silently overwriting newer versions of the same files. Since the dev stuff is full of git rollback transactions and it took me a couple hours to notice the problem, trying to untangle which files were overwritten by BTSync, which ones I had resaved on the dev machine since and which .Syncarchive revisions were the ones I wanted was basically impossible. It would have been a total disaster if I didn't have a 3rd machined powered off at the time which I could fire up with the wireless disabled and use a USB sneakernet to restore the original files on the dev machine. I can definitely see even more unmanageable tangles occurring in a BtSynced workplace with multiple people accessing shared folders. TL;DR - there really needs to be a way to designate a particular machine or machines' copy of a folder as a master copy. Whether it's a one-way data flow or bi-directional with approval of the master share owner, there really needs to be a way to prevent this sort of behavior without some sort of user-approval.