I had
Kobo Aura H20 over 30 days, but I did not like the slower browsing, loss of optical density of 2-3 letters page turns.
Whilе, Kindle PW3 - is retained even after 10-15 pages and more (without refresh), with very good quality of the text.
I dislike refresh every 5 pages

PW3 be refreshed each chapter - 10-20 pages and more
In Aura H2O - I liked it there very evenly / flat (no shadows, Blick) backlight, which in PW3 is worse.
Does improved display compared to the last model (AURA H2O)?
What are the main disadvantages?