humm... mine was preloaded with 8.1 and I have heard that the 10 upgrade is horrible.. somewhat afraid to do it because I don't want to blow up the only new computer I have ever had - -always built my own -desktop or bought used-laptop
Seriously, it's a breeze. Unlike all older versions, it just happens and when it's done it's done. No need to download patches for two days. Everything stays where it is. I've installed it on three computers now and no issues.
All you have to do is customize your privacy settings at install or Microsoft will have their eyes way up your rectum.