i love both.
NOTE TO EVERYONE WHO SAYS THEY TAKE TOO LONG: If you have TweakUI, you can speed up your menus. I have 'Fading Menus' and they pop up really fast (instantly, almost), but still fade in.
Also: the technical term is 'Alpha Blending', and is capable of doing alot more than fading menus. Basically, from what i know, it means that the GUI has the ability to slowly change one pixel from one color to another by taking the two colors and incrementally changing hues between them. Example: If your desktop is red, and your start menu is blue, and you click on the start menu, it will change each pixel in that area slowly more and more blue, slowly turning purple, and then even more and more blue, until all red is gone and it has arrived at the 'destination' color (blue). This is a big thing, i think. Win9x has no built-in ability to do this.
But i am no expert, thats just what i have concluded on my own.