This in theory would eliminate dithering on most modern monitors I imagine. This may be why windows 7 works so well for individuals. Its not having to falsely create those colors through the tickery of dithering.
I had a true 8 bit monitor. It was Samsung brand, not sure the type of panel, but it was when my lighting was bad and I was still using nvidia drivers that caused strain.
I am trying to set my system to 18 bit color depth today and see how it goes.
Edit: typing to fast, meant to use their in the title, not there