RE: Windows 10... Edge is CRAZY fast and uses almost NO RAM!!! I had seven tabs open, CNN, DeviantArt with an animated GIF, YouTube playing a video, Ello, and more, using no more than 22MBs of RAM. Not for each tab, for the whole damn thing!! It's fast, has a great UI, but is missing a few things.
Bookmark organization is difficult. If you show the bookmark bar, you can move a folder to relocate it, but if you drop it into another folder by accident, you can't get it back out. Not any way I could figure. You can't pin tabs. You can't create apps from tabs to launch from the Taskbar. There are no extensions at all, so no ABP, LastPass, or Xmarks yet.
But it does open almost as soon as you click the icon in the Taskbar. I mean, it's almost like it knows you're going to click on it. It's rather shocking. MS has done well to replace IE with Edge. Hell yeah!