I very nearly upgraded my Windows 7 PC to Windows 10 last night, having seen that this can still ("unofficially") be done for free, if you take the option to keep all files and apps. The reason I didn't go through with it is because it took about an hour to download, and then another half an hour to to sort itself out, by which time it was getting late and I didn't want it to happen and then not have the time to put things right afterwards.