OK...just updated my laptop from 8 Pro to 8.1 Pro through the store. That was the longest OS update I've been through....1 hour and 55 minutes. Mind you this laptop is a dual boot setup, so I don't know if that had anything to do with it. There is no option to customize the update to do a clean install like you could with windows 8 upgrade, that I could find. As of this moment, everything seems to be working as is should.