To get the optimum GMAT prep, use the Official Guide and the EZ Solutions set of 9 books. You'll get the best help, even more than what you'd get from a classroom course. You don't need anything else. I tried this approach and I can already see a big jump in my score in the practice tests. Join me in this forum and give me your feedback. Thanks.
I already have the EZ Solutions set of 9 books for the GMAT, great books by the way. I have a few friends for whom I have been trying to get these books but they were out of stock everywhere, but finally I was able to get them directly from the publisher, EZ Solutions (faster and cheaper). Thanks! Thanks!