I have two 15" HP Envy Touchsmart laptops and an MS SP2 Pro and upgraded all three of the from 8.1 to 10. All three upgrades went about as smooth as you could ask for. I was having a couple of problems on one of my Envy's and the upgrade to 10 fixed the problems. After reading all the problems that people are having upgrading their machines to 10, I feel very lucky to have no problems whatsoever. I have been using Windows since 3.1 and I can honestly say that in my opinion, Win10 is the best OS MS has put out so far. I hope all the people having problems can get them solved so they can start enjoying Win10 as much as I am.