Books are unbeatable.
We still have working copies of the first one, printed in 1454, or 564 years ago. Five hundred and sixty years ago! How old are the oldest file you can retrieve from your computer? How many old files you can't access anymore due to technological changes?
Yeah, I know. That is my point, your Kindle is a pointless toy that will prevent you from forming a library in your lifetime.
Paper book wins!