I don't know the science, but my experience is that my brain is simply able to process and retain information so much better with eInk than with LCD screens.

I started as a teenager with cathodic tubes, which were killing my eyes and bringing daily headaches; moved on to LCDs which stopped the headaches but still tire my eyes significantly (some of them literally make me cry after a few minutes); and then found eInk and it's so much better, I will definitely move to that once prices of large color monitors at 60hz get into my price range. I honestly don't care about power draw one bit.