Has anyone used the book ITIL Exam Prep Questions, Answers, & Explanations by Christopher Scordo?
I took all exams and quizzes through Exam 5 and was doing well enough that I felt confident to take the official 
ITIL practice exam where I also did well.
....Except that I have found every exam since then to be way more difficult.
Has anyone else used this book? Am I just imagining this jump in difficulty? Are they trying to over-prepare me for the foundations exam? Help!