I do not have the money or space for physical books, as much as I would like to have them.
e-ink displays are something that I love the idea of, but not the execution.
If I did a lot of reading outdoors - or perhaps traveled a lot - it would be great to have one.
But I have bought several Kindles now (Kindle 4, Paperwhite 2, and Paperwhite Signature) and never stuck with them.
For me, they just don't have enough contrast/sharpness, and I don't like how the Kindle in particular handles formatting (though it has improved).
In anything less than direct light, the page is duller than a cheap mass-market paperback.
I find that I need to turn up the front-light more than I'd like to comfortably read in the dark (which also makes the screen look hazy/milky), and I struggle to read them when I don't have my glasses on (a mild prescription).
It doesn't help that Kindle's library integration is (I believe) US-only. Or at least, it's not available here.
So I do most of my reading on an iPad now (set to automatically enable Do Not Disturb mode in those apps).
Text is very clear and sharp on them - so I can read without needing to have my glasses on in bed.
At night, I can use the screen filter to display red text on a black background, with the backlight turned all the way down - which is legible at far dimmer levels than a Kindle (for me).
File/library management is a lot easier too, if you buy DRM-free books or read public domain works.
And I can read comics/manga on the same device as my books (audiobooks too - though I use my phone for those).
I don't listen to a lot of audio books - mostly however many I can get free from Amazon for signing up for a trial (3-4 a year?).
I find that I don't absorb/retain what is being said nearly as well as reading it, and it's easy to zone out or get distracted and then have to seek back and re-listen to whole sections over again.
I prefer to focus my attention to the task at hand, rather than split my attention - so I don't often find myself playing a game or doing other tasks/chores while listening to a book.
I totally get the notion of wanting to be away from screens, but so long as they are high-quality ones (like the iPads with laminated displays) I don't find it to make much of a difference.
Really, the issue for me is spending all day focusing on something close rather than allowing my eyes to relax, more than the screen itself.