If the question is one DRM-free ebook vs. one physical book, I'd say the physical book. If the question is 100 vs. 100, or 1000 vs. 1000, ebooks all the way.

I'm really not concerned with a physical book deteriorating in my lifetime because I'm not going to leave it out to be weathered or bend the spine until it falls apart. Space is a bigger issue. Right now if I like an ebook I'll buy the physical copy to display it at home like art.