Ruling out the problems I had the first day I installed it, it is a pretty good browser so far. Thumbnails load a billion times faster unlike Windows 7, start menu customization is amazing with everything where I want it and how I want it. Everything overall reminds me of Windows 7 with a visual and performance redo. I was messing around with Cortana and while she's a bit inaccurate, she's quite amazing with what she can do.
Though on the second day my typing speed was impaired on Skype, I was able to change it tweaking around. There's something that unsettles me and it's the fact that programs are now referred to as apps. Having my Microsoft account linked to my computer's sign-in worries me a bit. What if there's something wrong with their servers and local sign-in is not available. And the fact that the Control Panel is way too simplified bothers me inside. But I guess that's what Microsoft was aiming at. Maybe I'm worrying about nothing.
On a side note, don't open Firefox with Cortana, as it will switch your homepage to Omiga Plus, a browser hijacker. But it won't stay that way when you open the browser normally.