Edit: I added the extracted PDF page for comparing..
Here are 3 pictures I took of the PDF Star Charts I tested on my DX. Sorry the pictures are not that great and do not show the greatest quality. I had trouble with the auto focus. I'm a point and shoot kinda person. The flash washed them out and when I turned it off; I had to color correct for the florescent lights, so that also changed the quality..
Overall, I am loving the PDF support. As noted by other threads, some of the PDF's are hard to read in portrait, but look much better in landscape.