Recently upgraded from an ancient paperwhite with a near 600 week streak to a Pocketbook Inkpad Colour 3. I would consider myself to be a heavy user of ebooks, its the only way I read and I read at least an hour a day every day.
Decided to upgrade as it was time to replace the battery in the paperwhite, I wanted something with a faster page refresh, a larger screen, and I wanted a colour screen for comic books.
As I have gotten older the text size I read with has increased, so a larger screen is better as I have to turn the page less often, and a faster refresh rate I am waiting less when I do as I am turning the pages more often.
I am very pleased with it so far, its much nicer to use than my paperwhite and it feels good to be away from amazon. Obviously it is not going to compare to a decent tablet for colour depth or refresh rate, but I wanted eink for the battery and day light performance.