I updated late last night and it was something of a disaster. First off it took at least 2 hours to complete and then I found a few things broken. Classic Shell had to be completely reinstalled, Comodo wouldn't load and also had to be reinstalled, my video driver also had to be reinstalled since it reverted back to the generic one that only supports 1024X768 resolution. My settings to skip the password on login also had to be redone. Then I had to remove the windows.old folder again to regain almost 6gb of space and do a boot defrag with Puran because my registry was now in 45 pieces and the drive was heavily fragmented. I also had to turn off the Enhanced Protection Mode in IE11 to get Flash and Java to work. I think everything is working right now but it took at least 5 hours to get it that way. The performance is no better than it was and the new features, for the most part, will never be used. I'm thinking I should have skipped it.
One thing I did discover is that the need for Classic Shell is almost eliminated. The new Start button does not only take you to the "Metro Screen" but if you right click it, gives a multitude of shortcuts to things like Control Panel, Device Manager, Command Prompt, My PC settings, shut down, and many more things. If you also add the Desktop Toolbar to the Task Bar, you have access to almost all of the Start Menu. All your programs are listed and accessible as well as other settings. The only thing I was missing was my browser favorites and the only reason I felt a need for Classic Shell was to get them back since IE is my default browser. If you use something else, the favorites access won't be missed since it only works with the ones stored by IE.