Excellent if you're starting from the basics and don't have a tight schedule

I went from 660 (based on official Gmat prep test) to 730 by using e-Gmat only. Took 3 months.

It has a LOT of material, both quant and verbal, and both theory and excercises. It also has a dedicated platform for testing which has official questions and questions similar to the official ones developed by e-Gmat. The platform has excellent statistics on your performance which are very helpful. It has as well 5 full Gmat mocks.

The downside is that there is just so much material and time estimates provided by e-Gmat are way too optimistic. Questions developed by e-Gmat are usually harder, more ambiguous and take more time to solve than official questions, consequently, you may believe that you are worse that your actual performance. The courses have material which may take hours to complete but relate to only a small subset of actual questions in the exam (so small in fact that you may never encounter such questions in any prep test or the official exam).

While e-Gmat theoretically breaks the learning curve in three stages to minimize the risk of you taking too much time reviewing stuff unnecessarily, the courses are actually designed for those who start from 0.

My word of caution if you choose e-Gmat is to be very strategic about how you decide to use the material. Always think about ways to skip parts of the study plan (while not affecting your learning). For example, you may skip pre-assessment quizzes, you may just skip to the summary on many topics, or the theory quizzes. Other topics may be skipped completely. You may also get worried because your score with e-Gmat questions is not as good as you may want... don't, rely on the score you get in the official questions. If you decide to follow the recommended e-Gmat strategy of first doing all verbal and then all quant, you may find that by the time you start doing the mocks, you have lost some skill in verbal questions.

All of this, of course, depends more on you and not so much on the side of e-Gmat. I think I could have gotten the same score in 2 months instead of 3 if I had been better at approaching the course material.

Overall, if you take into account this precautions, I do reccomend e-Gmat.