Ebooks are translated and if you don't get a good translation the published book doesn't look good. Having said that, an e-book can be better than a PDF file.
I love E-books. I have a Nook Color, so it's really an e-reader that pretends to be a table but I LOVE it. I have over 1000 books on it, probably paid for 40 or 50 of them. I always have something to read because it syncs with my Android phone. It's great for all the doctor office waits!