Review

I took the e-gmat verbal + quant course, including the GMATclub tests. The main purpose of taking up the course was that I was struggling with improving my verbal score. I was stuck at the V30s and my target was V-40s. The best part of the course was the SC- the classes were followed by short practice exercises, which I believe increases retention rate. The CR part was excellent in terms of understanding the different parts of an argument, the different kinds of questions that can be asked and mainly getting to know the traps involved in official GMAT questions. The RC course was good for learning the way to understand any given passage, and increasing retention while reading anything.
Quant could be helpful for people who have lost touch with the subject.
The mock tests from e-gmat and GMATclub, combined with other tests (Veritas, Manhattan) are probably enough when you have an understanding of the Official guide.
Overall, it was a pretty helpful course. It helped me in navigating through the traps and nuances during the real GMAT.