I've liked this video comparison, yet posted in here:
( Best Color eReader: Boox, Kobo, PocketBook or Bigme?)
As mentioned in the forum already, the pics or videos often does not provides an accurate feeling about the screens and them colors.
Can I misuse to ask if on a color device (where the 300DPI drops at 150DPI on color reads) is it possible to use them as a B/W but may choose other color's backgrounds (in place of using the frontlights)? If so does it drops the pixels ratio anyway?