They're both sewn. There's not really any gutter loss to speak of in #4; there are a few pages where the layout is kind of tight, but it's not that big of a problem, as in some earlier volumes. Obviously, Vol. 5 lays much more flat, but 4 is still pretty good! I'm not the one to ask about art or color repro because I never did own the original comics. Someone else on this thread will have to compare with the originals. That said, it's my opinion that both volumes look great!