Hi,Koemi.I promised that I will tell you what is the difference of the two artbooks.
Devil May Cry 4 Devil's Material Collection - has early drafts of DMC4,many CG artworks for monsters and characters,and exclusive artworks such as Dante with Yamato,Super Dante,and Super Nero.
DEVIL MAY CRY 4 MATERIAL ARCHIVE saber of savior - has lyrics for several songs in the OST like Out of Darkness,first public exhibition of making cutscene movie,Scenario pages,character guide,weapons and monsters.A DVD is included,although i don;t know what it is for.
I bought the Devil's Material Collection,and it is worth the money.Sorry for the late info,because i just bought the artbook yesterday and asked the anime shop owner about the other artbook.Hope it helps you.
And I do have a story for my Concept. Dante's stuck, about to be sacrificed... The whole Vergil returns part, and Nero entering to save Dante... It's all there In pieces at the moment... Just be patient, I can't write it all in a day :lol: I'm not that good