I used the 2nd edition book (GRE subject math exam), and from the sounds of other reviews, this book is about the same, which means it is an excellent book to use (and it is an excellent price). I used this book during the summer for several weeks to prepare for the GRE, including making note cards of most definitions and working out all of the practice problems. I then didn't look at this book for 3 months and then my GRE finally came around and I reviewed for a few days with the book, primarily working problems. The problems in this book are tricky and train you to find the tricks for problems on the GRE.

After having taken the GRE (Dec, 2005), I can say I would have faired poorly without the preparation of this book since I would have missed so many little tricks that came in useful and I would have gone through the test without carefully doing every problem. Having used the book, the tricks for nearly every problem on the GRE were easy to see. The book problems seemed to have a general theme: if your approach has overwhelming computations, look at the problem for a trick, as this book will teach you to do (and some of the problems it gives have a trick that can be molded to other problems).

Some other books to consider looking at for subject review (check out from a library -- not worth buying unless you want more info than you need for the GRE):
"Topology" by Munkres (I thought the GRE book was insufficient to get a good feel for topology without previous study.)
"Complex Variables and Applications" by Brown & Churchill (I was a bit fuzzy on residues from the GRE book alone -- Brown & Churchill's book is worth reviewing.)
Both topology and complex are small portions of the exam, so reviewing these topics may not be worth the time unless the GRE book is no help to you.

This is a great book for preparing for the math GRE. Far more useful in terms of reviewing/learning material than the REA book. It has only one full length exam, but many practice problems, and every problem in the book has a detailed solution.
WARNING: This book is essentially the same as the 2nd edition, with some minor errors fixed. As far as I can see, there are no new excercises, and the practice exam is basically the same. I would not recommend getting it if you already have the second edition. This is why I only gave it 3 stars.

I am planning on taking the Math GRE subject test rather soon. I was given the 2nd edition by a friend. I did a quick comparison between the editions, and they seem to have the exact same material.

Has good review material.