There's a nifty feature in Pro Tools First that we've discovered as we have been putting it through it's paces and thats a version conflict feature.
What that means is that if you've been working on a track on one machine and then come to open it on another then Pro Tools First will alert you to a mismatch between the copy in the cloud and the local cached copy on the machine you are trying to open it on.
You can open the local version to see if it is the most up to date, unfortunately there does not seem to be any option to listen to both copies and then make a decision on which on to keep.
We are guessing the same technology will appear in Pro Tools 12 at some point, so this should be an indication to how this function may work.