until the Kindle Paperwhite, I could not stand reading eInk screens because of the low contrast.
I keep seeing people say this, and it makes me wonder if Kindles have really crappy contrast, in general? Even without a backlight, my Kobo Touch has better contrast than most paperbacks I own.
My experience is; not really. The contrast on my Kindle Keyboard (about two years old) is actually no worse to my eyes than a printed hardback book. Really; I can barely see much difference between them. I find the contrast perfectly acceptable for reading, and definitely less straining than trying to read on a backlit colour LCD. I honestly think Amazon made a very conscious decision to make the contrast and screen "colour" to match a printed paper book as close as possible. Most people liked it, but some like GP did not and preferred to have a screen with greater contrast. While the "paperwhite" is definitely better, it's not an upgrade I'm going to sink money into at the moment because I just don't care. My Kindle is definitely good enough, and I'll maybe upgrade when I either break or lose my current Kindle.
I think the people who complain about the contrast are those who think the paper in the average hardback or paperback is actually white... it isn't!
It's a naive, domestic operating system without any breeding, but I think you'll be amused by its presumption.