re: 'Secure' Cloud File Sync Is The Wrong Move
For what it's worth, one of the organizations that I used to work for was a small component of a much larger company and the much larger company defined security standards that we had to follow along with the various forms of compliance that we needed to handle.
At one of the quarterly IT leadership meetings, there was a presentation by the corporate information security guru about the product that all of the components were going to be using - storing data in the "private cloud" (although, back then we weren't visionaries and simply called it a co-location data center). After the demo, the discussion turned to other products that were available and the message was delivered that any other data storage facilities outside of the local security perimeter or the "private cloud" would lead to serious repercussions, including immediate termination. As a precedent, management had just terminated the ENTIRE IT staff of another component organization when it was found that they were using a commercially available, non approved solution.
Moral of the story - the data that most organizations have in their possession usually exceeds the worth of the organization and to trust that to an unvetted, insecure entity is corporate suicide.
Investigate these solutions, their vendors, the whole 9 yards. At this point in time, I always assume that any data that leaves my physical location is open and available to the rest of the world.