83-640/83-642/83-646: Study Material

Gentlemen,

I'm curious to see if people know of a good single book for each of the 70/83-640/642/646 exams. I liked the Exam Cram series for A+ and Net + so it would be awesome if there was a similar book for R2. I'd like to read three smaller books, the current book I have for the MCTS covers all three of them but is poorly structure.

Thanks in advance!