The best foundation for GRE prep
My biggest worry about this product was that perhaps the practice tests would be contrived and undiagnostic of actual GRE performance. However, I took the actual GRE this morning and was pleasantly surprised to find that my scores were roughly the same as the scores that I had achieved on the practice tests provided with this guide--I'm impressed!

I would recommend this product as the foundation for any GRE test prep. Not all of the tips they provide are brilliant; you'll be able to pick and choose which ones you find helpful and which ones you find needlessly cumbersome. However, it provides a good overview of the typical GRE vocab and math problems and, if you're like me, you'll be grateful (and a little embarrassed) when they point out blatantly obvious tips that you hadn't previously thought of (e.g., creating a verbal bridge to join analogy terms).

Of course, I recommend using other products to supplement the material in this guide. The free GRE Powerprep math review is a good reinroduction to basic math concepts if you're rusty (I went through it prior to starting on this book). I also used Kaplan's "GRE Exam Vocabulary in a Box", as well as the vocabulary hit list from The Princeton Review's "Cracking the GRE". Using these products, I was able to obtain an extremely high verbal score and a decent quantitative score. If you want a perfect quantitative score, you may want to go a bit deeper than I did. However, the products that I've mentioned should be enough to get you a verbal score in the high 90s.

Concepts explained well
Watch Video Here: http://www.amazon.com/review/R1DOFG0KLJYSMB Getting Things Done (isbn 0142000280)

Don't Like to Read, Then Don't, Listen!: How to Turn Any Type of Text Into Audio Files That Can Be Read to You! (isbn 1438252455)

Effective and helpful
I'm going to start my third year of college soon and have already registered to take the GRE. This book is a MUST HAVE because ETS has changed the format of the GRE and this book covers all the changes. The book contains a lot of strategies that I could have figured out for myself...but the practice problems and tests are very useful. This is a priceless resource if you want to score high because they give you a list of the most common vocabulary words that appear on the GRE...I'm sure nobody wants to randomly memorize words from a dictionary.

Excellent
This is an excellent prep book for the actual gre. Their vocab and math prep workbooks are also excellent.

Very Helpful
This book had everything I wanted to help me study for the GRE. I enjoyed the helpful hints and tricks to mastering each section, and there are more than enough practice tests available to help me prepare.