This book is by far the best prep book out there. The strategies were amazing! I did not use it for vocabulary, but I did use it for almost everything else. The SAT is all about finding which methods work for you. This book gave me amazing results. I took the SAT only once, and I got a 2400 (12 on the essay). I found it to be extremely helpful with grammar, reading, and mathematics strategies. It gave some really interesting methods of viewing the SAT (especially the reading section!) One thing which I thought this book did phenomenally well was the grammar review. This can be a very dry subject area to learn, as you have to memorize the rules of English grammar. What made this resource better than all of the others was the informal manner in which it presented all of this dry content. The conversational style used by the author greatly simplified the material and made it easier to digest. Also, the mathematics section (especially geometry), had some interesting tricks for solving the harder types of problems that show up on the SAT.
Overall, I found this book to be an amazing resource. This was the only "prep book" that I used. Just take some practice tests using these strategies and figure out what works for you, as each person is different. :)
I highly recommend this for improving your SAT score. Remember though, that SAT scores are only one part of the admissions process.
Based on what I have seen through my experiences in high school, after a certain point, test scores and academics do not seem to matter. The difference between a 2400 and a 2280 is just a few questions. For this reason, I believe that any score above a 2280 is considered to be outstanding. What this means, is that if you score anything in this range, do not bother to retake the exam. There have been a few extreme cases where I have seen people do this. You are better off spending your time on other pursuits, rather than trying to achieve a perfect score after getting a 2300. As a statistic to confirm my views, scoring a 2280 puts a student at the 99th percentile of all test takers.
Overall, this resource is a great way to prepare for this challenging exam. I highly recommend it.