The question is how often do you to reread the same book?I think, not often.
And did you think about environmental factor?

Modern technology now make it possible to have always with you about 3,000 books. My object is it installation. I would call it: One book in the other.
I have a dry facts that should bring you to the right thoughts.
To produce one book needs:
150 kg / 0,63 / 2 / 0,5 kg = 0,0430 trees
One e-book can contains at least 3,000 books
To produce 3,000 books needs:
3,000 books x 0,0430 trees = 13 trees
One e-book cost at least 50 – 60 $
One book cost at least 20 $