Im intrested in getting a Berserk Artbook but im not sure which one is the best. I also heard there are posters which come with the artbook which i really want to get.
My recommendation is the Illustrations File, with the Visual & Story File as a second choice. The Illustrations File is the only one that has a real poster attached, one side representing Guts and the other Puck. It's not all that big, though (3 pages long, 1 page wide). Other than that, the artbook for the TV series has a 2 pages wide poster-like supplement at the end, but it's not that good (not done by Miura).