I'm actually not on windows 10 yet sadly...
the test machine I had running windows seven ultimate was completely trashed by the upgrade.
apparenyl during the process of enlarging the system reserved partition, Microsoft decided to not let it check to see if it was writing over another primary partition first. This resulted in the partition where my windows 7 and windows 10 upgrade media becoming unbootable.
After trying to recover the partition using WinPE and Diskpart, I still couldn't get it to restore because the system reserved partition had already been rewritten at that point, and the factory image destroyed, as well as all of my restore points.
I was smart enough to save the key beforehand, so maybe one day I'll call up MS support about it, but seeing as it's OEM, I doubt they would do much. In the meantime, the test box is currently running Linux.
Your slightly annoyed Wolf
~Era