My original 1501 (and hubby's) are perfectly white/gray. Had a problem with mine last week and now have two replacements from same batch that have yellowish tone to entire screen, with green/pink blotches. Ugh.
Need to call them, yet again. They must recycle the returns around and around, in hopes someone will accept them.
I could live with the colors, but the yellowish tinge to the screen makes the contrast considerably less than on an actual 'white' screen. So, books with non-standard and thin fonts become much harder to read.