A couple of things I detest about Vault.
One it still relies on user input to update who, what, and why the file was checked out to be edited MANUALLY.
Which if people were doing this out of habit already there would be no need for a vault like product to exist.
The other being the once a user checks a file out, they can simply close the file, and it never gets checked back in.
So there is still a lot of MANUAL input required for vault to really do it's job.
The other MAJOR issue as I, and now SINC have pointed out, it is NOT and does NOT provide any form of project associativity, or functionality for users of Civil 3D. It also doesn't allow sharing of Point data as a Data shortcut; still.
If they (autodesk) would listen to the customers, admit the shortcomings of applications and REMOVE or IMPROVE based on that feedback I wouldn't have the same complaints today about Vault as the First time I installed tested, and then removed it from my computer.