Sometimes you can’t do a clean install of the OS and move to Win8 RTM. One of my machines I’ll be using for an ongoing project it’s in that “perfect” operating mode – except for the RC versions of Visual Studio 2012.
The following links provide the upgrade paths as needed (note that with Win8 – must move to RTM of Win8 to get VS2012 RTM.
How to uninstall Visual Studio 2012 Release Candidate
Upgrading from Visual Studio 2012 RC to RTM