This project is useless if they don't figure out a way to serve files without both machines being turned on, there is also the problem of syncing with multiple clients beside that.

I see two key use cases that could cause trouble:

1)a co-worker turned his computer off and went home from work, the syncing couldn't complete even if only a single doc was left

2)Because there is no central server if all of my coworkers in a distributed team sync with my new shared folder at the same time, it is required that I own a connection capable of supporting that kind of traffic, because it would be almost the same as streaming a video to multiple users, not to mention that I would probably have to avoid to browse the web for pretty much anything else in the meanwhile.