Tried it last night. I installed the latest driver then unchecked the box. After that I tried to open my games and it wouldn't. Oblivion didn't recognize the video card and BF42 just flickered the screen black for half a second then went back to the desktop. IE ran slowly because the graphics were loading at a snail's pace.
Putting the old driver back and rechecking the box fixed everything again. I think, for now, I'll just stick with this as I really don't run into any problems.