Well I mean; all things considered it's not really THAT dreadful. Windows 8.1 was the spawn of some ancient god and a troll so I'm glad to have that crap out my...window...So it'll be necessary in the end regardless? ;n;
Maybe a month or two?
Bad puns aside I don't really mind Windows 10. I like the interface more, Edge works (somewhat at least but I still prefer Chrome) and it's easier to find the core settings in your computer to do some of the things that were harder before: like cleaning up your files or just fixing drivers and such. It just needs a bit of time to be fixed up after people use it to find all the things that NEED fixing. But I don't see a reason not to upgrade while it's free. I've been avoiding using my bank account on my computer because of people talking about security issues (not sure whether all that is true but better safe than sorry) and the fraud that someone tried to pull on me a couple months back BEFORE Windows 10.
So if you want to upgrade and find out what you do and don't like then I say go for it. Unless you're in love with your current OS then there's no reason not to. Just be sure you've got the day to work with it and make sure you update your drivers and all your stuff works.