GMAT Club CATs - Best non-official CATs for Quant

I gave my GMAT on June 17, 2016 and scored a Q50.
I have always been comfortable with Math but struggled with GMAT Quant. DS, especially, gave me jitters. While navigating through the forum one day, I came across a debrief from a person who had scored Q51. He attributed his score to GMAT Club CATs. I researched some more and read a couple of other reviews. I could not find one person/ review who wrote negatively about these CATs. I got lucky when I got access to the CATs for a 14 day period for participating in a survey program. After that, I extended my subscription for three months by redeeming 25 kudos.

The UI on the GMAT Club CATs gives you a feel of how the official CATs work. The quality of questions is top-notch. One has to understand the fact that these CATs are meant to assess your weaknesses and build skills for handling different types of questions. These CATs do just that. Each question provide you with excellent explanations and a link to the topic where these questions have been discussed over the years. The analytics/ statistics help you evaluate yourself. Statistics such as average time for correct answers, average time for incorrect answers, least time spent on a question (correct and incorrect), most time spent on a question (correct and incorrect) etc. help in building ever so important time management skills.

After you have completed a CAT, there are various tools to help you review it. For example, you can write notes for each question you attempted, you can bookmark any question, you may wish to re-attempt in the future, and if you have reviewed a question thoroughly, you can mark that question as reviewed. There is also an option to create quizzes from the bunch of questions you have already attempted. In fact, if you don't have time to complete a CAT or don't want to attempt 37 Quant or 41 Verbal question in one go, you can even start practicing by creating a quiz from the humungous pool of questions.

All in all, these CATs are worth your time. Especially Quant CATs are flawless with excellent quality questions and explanations.