Is there any empirical data on the comparative contrast between the words and the screen background on the various readers? I've read that the new Sony Reader has better contrast than the older model, but how much better? Is it possible to compare the displays with a densitometer or something? I'd be curious to how the various devices fare in this test. Does anyone have solid information on which (ePaper) display has the best contrast? I have a Sony Reader PRS-500, and as much as I like it, I'd like it a lot more if the background were closer to actual white paper in appearance.