I have published POD paperback non-comic books through CreateSpace, and non-comic ebooks via Amazon.
I did not choose to publish my graphic novel as an ebook via Amazon, because they charge a "data-charge", and although for text the amount is negligible, for 302 full color pages proved to be so expensive, it didn't seem worth it.
I did not choose to publish my graphic novel as a POD paperback with CreateSpace for essentially the same reason. Too expensive.
Black and white artwork is probably more feasible.