RE: Workarounds
100% agree.
Like nickrw, I have also unpacked the .box files and (after searching briefly via Google - try "Windows 7 upgrade bootable iso" or similar) managed to find a cmd command to make the files into a bootable .iso file.
Burned to blank media and was up and running with my install.
This DVD can then be used for as many installs as needed, providing you have purchased a key from Microsoft.