Remember on Windows XP when there's be arguments over who was faster? Msstyles or WindowBlinds?
In the Windows Vista era, such arguments seem almost quaint as the massive performance advantage of WindowBlinds over Aero is undeniable.
Where it really shows up is in resizing windows.
Winter Wonderland MyColors theme
Try it for yourself. If you have Windows Vista, load up Aero, open up any program (the more complex, the better) and resize it with the default Aero. Then load up the most obnoxious, most complicated WindowBlinds skin and try it. The difference is pretty significant.