Fullmetal Alchemist Volume 06: 08/08/11
Fullmetal Alchemist Volume 6 by Hiromu Arakawa finishes the Rush Valley and Dublith plots. It also gives background on how Ed lost his arm and leg and how Al lost his body all together. It also introduces the start of their friendship with Roy Mustang.
Ed and Al's time in Dublith is an interesting break between the original anime and Brotherhood. In the first anime a lot of time is spent replaying Ed and Al's first trial as apprentice alchemists. It involved a month of surviving alone on an island. They are kept watch on (but not helped) by the husband of their teacher. In Brotherhood his involvement on the island is completely removed so I was surprised to see it in the manga. The second anime, while much closer to the manga, is not a perfect adaptation.
Besides showing how the brothers went from competing all the time to being as close as they are in the present day part of the story, the book shows why they are so hell bent on finding the philosopher's stone. The transmutation of their "mother" is as gruesome as ever, although a little more tasteful when rendered in black and white.
Finally there's Roy Mustang who comes to them on word of there being a pair of alchemy prodigies in this out of the way town no one has otherwise ever heard of. In the first version of the anime the boys go to Roy instead of him seeking them out. He also (and completely out of character) has them board a train he knows is in the process of being hijacked. Given Roy's soft heart but drive to make his way to the top, him seeking out new pawns makes way more sense than him putting untried children into a dangerous situation on a train.