I had started with Mikalai Zaikin notes. Due to very short time for preparation I switch to Specifications so that I do not want to miss some points. The Mikalai Zaikin's notes are so good and cover all the aspects of the exam. Anyone can refer these notes because the specifications are very heavy to understand.
Niranjan I have used the same book you mentioned. But can not go through all the book do to the time limitation as the voucher is expiring on 31 January. It contain lot of example to understand the spec. The Persistence spec is very criptive and you have read each and every line carefully to understand the concept. This book given the descriptive examples of each of these so very easy to understand. Very good reference book and it is best companion to specification.
About the exam , it was very simple compare to the another Sun examinations. It is not much detail level. If you have a strong conceptual knowledge you can through the exam.
I do not have any previous experience to EJB 5. I have studied very high level for the SCEA 5 Beta Exam. The easiest part for me the Persistence API as I have 7/8 years work experience in RDBMS. I only learn the entities concepts and the Path Expressions. The Query language is easy for me.