Since all this thread is about READING, nothing beats the Paperwhite 2013, in my opinion. Plus, the HDX 2013 with white text on a black background (blue borders are GONE with that setup) beats all other devices in dim light like sunset. The beautiful music coming from the HDX 2013 at sunset makes the reading experience SUPERB.
The keeper is that the best eBooks for my needs (history and biography) at the lowest prices come ONLY from Amazon.
PLUS, I doubt if any other eReaders (tablets or otherwise) has this kind of site to review, memorize and access ALL notes and highlights for our Amazon eBooks:
https://kindle.amazon.com/your_highlights