Anybody with experience with the current 13" with HD 3000 integrated graphics and a 27" Cinema Display or Dell U2711 running at 2560x1440. I know that the 13" CAN output to this, but does it do it well? I've read reports that moving and resizing windows is often choppy. Obviously, gaming is out of the question for the most part. But can it handle Expose at full framerate, smoothly move windows and play 1080p video without stuttering? I'm going to get a 27" screen and don't need monster graphics, but I do need for these things to be buttery smooth and not be laggy and choppy on the external screen.