A couple of years ago, I took part in an official Microsoft course in Administerting XP. At the end of the week (with previous experience of XP), I decided to sit the 70-270 exam (I had a free re-sit).
I failed the exam by a few points. What I realised was that the book provided on the course was for that course and not necessarily for the exam.
After a bit of searching about, I came across the Sybex book. It was great. Very well laid out, easy to read and with excellent end of chapter review questions. The book prepares you for the exam and filled in the gaps from my Microsoft course.
I sat the exam a couple of weeks after the first one and aced it!