Good question. I've spent the better part of 2 and a half decades building my personal library. I really like hardbound books and have many of them (I have around 6,000 books) from Easton and The Folio Society and others. But what matters the most to me is what's between the covers. So if I'm trying to get the books I want and can't spend as I wish, then I get paperbacks (with 7 kids, three animals and a wife, I usually can't spend what I want just for my wishes). I carry a book with me at all times. Learned that in the Army. Too much waiting time to be wasted. Got to have a book handy for those times. Usually, a book I carry out of my home study is paperback. Smaller, easier to carry, not a big deal if it gets wet or stained or whatever.
I've never read an e-book. Though one of my heavy-reading friends from the Army swears by his kindle. He loves the back-lighting for darkness.
Kelly