Did this today. It was a fairly clean upgrade, with only these exceptions:
- VirtualBox would no longer launch so I upgraded to the latest version, v5.1.18, and that fixed it.
- Microsoft Outlook (part of Office 2013) errored upon launch. I ran the Inbox Repair app, which found a bunch of errors that I had it fix. Then Outlook worked fine.
- A few file associations got dropped (e.g., for opening PDF’s, PNG’s, etc.). I have to think this was on purpose by Microsoft.