I'll choose paperback anytime. I've tried reading ebooks, a couple of times, but it's really not for me. My eyes get watery after a page or two. I am a big fan of detective, mystery or CIA/FBI inspired stories. When I can't find a good book, after doing my weekly rounds of my favorite second-hand bookstores, I borrow my sister's Johanna Lindsey books.
What about you, do you prefer holding a book or reading pdf files?