One thing that I've often wrestled with in assembling my study materials is which version of a book to buy/get. Here's my review comparing the two different versions of the Kaplan GMAT 800
2004-2005 edition vs. Kaplan 800
I have got both copies on temporary loan from different sources. I started reading the latest edition (2005-2006). The book comes without CD. It has no introduction to the GMAT but jumps right in. First there are three sections of the book dealing with the three Verbal topics. The Math sections show up later in the book. I have just finished reading the first Verbal section - it is on Critical Reasoning (CR). The section itself consisted of 3 chapters - an introductory chapter listing the different kinds of CR types (per the book's own classification), a second chapter which lists CR questions where the type gets mixed (to make things difficult for the test taker) and a final chapter which just consists of 28 CR questions in sets of 4 (4 Questions followed by detailed answers to the four questions). The answers to each question in the entire section are very detailed - anywhere from between half a page to a full page. It clearly lists which answer is the correct answer and why and also lists some reason (tho' these can be short) why the other choices are not correct.
I went back and checked the 2004-2005 edition of the book. It is identical in terms of the questions - every single question in the Critical Reasoning section is the same. From what I could see the explanations are the same too.
I will update this thread with other section details as and when I finish.
Hope this is of help.