So we tried DropBox and..... if its for your own personal use maybe its OK but using it with others shows its not secure. " You can't share a folder within a folder " Oh yes you can and when confronted with the facts AND that the invited guest can see UP the directory as well as across it ..... admin just folded and admitted that its a bug. Not good if you don't want people poking around in your files.
We found Tonido and its really good. Perfect for what we need and sticks it to every other "Home Server" "sync'd files " type product out there AND ITS FREE.
In common with all IT start ups ( even if they are a few years old ) the documentation is rubbish, the wiki not adequately supported and the forum full of geeks trying to write code or trying do do stuff outside its scope.
Having worked on it a few nights now when the baby is sleeping, so I can concentrate, it has come together nicely and the Workspace feature is a dream if your running teams on projects all around the place as we are. Just remember to set Sync to manual ( 0 ) in Files or you can wait for ages until it activates.
I would happily pay for this product ... if they had a full and meaningful manual.