If you travel a lot it's nice to listen to CD-ones. Just relax and enjoy the listening.
But in my opinion a printed book in perfect for me. Since childhood I've read dozens of books. And every time I hold a book I'm amazed and can't help opening it. You can see the letters, turn pages and even smell them. Oh yes! The smell of the book is unforgettable!
Time goes by. But I hope a printed book will stay forever!