Best Quant Prep

I was struggling to improve my quant just the few extra points to get my GMAT score in the mid 700s range. Practice test after practice test I could not improve on the topics that hurt me most - probability, combinatorics, and work-rate problems.
I switched over to TTP five weeks before the exam and did not take another practice test until the week prior. I improved from a Q46 to a Q49 by the end of my studies with TTP.
TTP does a great job breaking down the quantitative topics into different modules. I went module by module focusing only on the medium to hard problems, timing myself like I would for the real exam. The modules also have thorough video based solutions.
The cumulative reviews after each module were immensely helpful in jogging my memory as to topics I had already covered.
And finally, Jeffrey and the team provide nearly instantaneous live feedback to any questions you may have. Highly recommended.