I just bought this book and am quite impressed with it. To be honest...this is the quickest way to achieve cisco certification. I used the exam notes book for the CCNA and passed with room to spare. I did buy the "big" Sybex study guides which were way too boring, so in my honest opinion the exam notes is the way to go. This CCDA exam notes is right to the point and there are no extra fillers. There are a few typos, but nothing out of the norm. I will be taking the CCDA on August 16, and most of all I'm confident I will pass.