I took a 9-week course in Spring 2014. The materials provided by Manhattan GMAT are invaluable. I found the set of math books to be extremely helpful -- the books are separated into various topics, such as Fractions/Decimals/Percents or Word Problems, and provide easy-to-follow steps and quick tricks to solve these problems. I had a very limited understanding of these basic math concepts (I hadn't taken a math class in a few years) before taking this course and the books quickly brought me up to competitive levels. The Quant problems are very difficult which also helped prepare me for test day. There are also plenty of practice problems provided both by Manhattan and MBA.com's Official Guide of problems. I found the online resources unrivaled with any other program. The online resources provide a platform for you to time yourself and plug in the answers to problems from the Official Guide and then synthesize all of the data to highlight weak and strong points. The online practice tests have similar tools, such as showing areas where you move too fast or too slowly, or where you need the most work. I found that incredibly helpful as I was able to focus on my problem areas for most of the course and then honed in on my strengths in the days before the exam. The IR sections are incredibly difficult on Manhattan GMAT, but again, they prepared me for test day and I received a score of 8. My instructor for the course (Abby Berry) was professional, energetic and had a genuine interest in each student. She tailored the course to fit the class's needs rather than following a rigid and generic structure which I found very helpful. Manhattan GMAT helped me bring my score to levels competitive with the averages of the top five business schools and I am very satisfied with my outcome. I would highly recommend this course.