If you really want something around 10" I would recommend to look at the ipad, too. I was hesitant at first,too (I still disapprove to apples closed ecosystem), but it's just plain awesome for colored, heavy formatted pdfs. It's faster than my eInk devices for pdfs and I can easily sit on the couch and surf mobileread, too.
Battery life is decent considering it's not an eInk device. With my usage (reading, surfing, an occasional round of solitaire played by my wife), I get about a week of battery life. Sometimes it's shorter. That's when my wife can't get off playing solitaire
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For reading plain text, I still prefer my dediated eInk Prs600.