I have been using 8.1 since release without activation and wondering if 10 is the same. There's a watermark on lower right corner, but doesn't bother me
Yeah, it's pretty much the same. I don't know why you'd want to do this though, lol. It's a free upgrade, after all.
Yup. You get a new and improved "Activate Windows" Watermark that shows above all other windows and can't be removed by watermark removers (yet) tho
You can't access personlization settings like theme, color & wallpaper. You can use other features though.