It's a bit of a quirky device... As a book it works pretty well, though not as well for paging through of course, but much better for text by weight and volume. If it cost much more I'd be annoyed at its limitations, but given that you can get some books free or near to it, and all other books at a fraction of their paper-price, it is a good deal as a portable bookshelf, or should I say, library... Recommend it? Do you read a lot of books? Do you live outside an English speaking country? Do you never plan to get used or library books anymore because of possible lice infestation? Do you go on long trips and are tired of carrying several books at a time to ensure reading? There you go.I do miss print books, but having the device it's hard to pay double for print. I find myself reading it much less than I did, but that's more having a second child, and a smartphone I use for reading news on the train, than issues with the device. Smartphone: there is no comparison. The Paperwhite is a good book reader with a seemingly limitless battery, if you keep wifi off; the smartphone lets me do everything else, but only for about two hours. When I travel I take an external battery, but have never had to use it on the Paperwhite.
The device also allows me to carry on it, at all times, a mountaineering and camping techniques book, a book on emergency expedition medicine, an exhaustive bicycle repair book, a complete Shakespeare, half a dozen issues of Granta... Yes, I could put all of these on a smartphone or a tablet, and even use black screen with white print both to use less power and relieve my eyes, but I'd have to worry about the battery much more. Besides, when on an Internet connected device, you're probably going to get distracted from your Dostoevsky.
A smartphone is now a given, so if you're going to buy another portable device you do: for a bigger screen, for a longer battery life, or for a keyboard. If you need to type a lot you still want a laptop, but you might make do with a tablet and keyboard. If you don't need to type a lot, but want a media device as much (or more) than a reader, you get a tablet. The laptop, smartphone and tablet suck juice, so you stay close to civilization even with an external battery; you could go further afield with a solar charger, if you don't need a reliable power source, or mind the weight. An eReader gives you a week of reading on one charge, and gets you off the Internet.