Target Test Prep is really helpful for Quant

I took the GMAT four times in the past year. My first score was 700 (45Q 40V) and final score was 740 (50Q 39V).

Target Test Prep helped me improve my Quant score from Q45 to Q50 in about four months.

The program is a lot of work, but if you work through all of the lessons, example questions, and tests, I'm sure it will help you improve too. I only completed about 54% of the program because there is so much to do (I think I completed 70% of the lessons and 50% of the questions or something like that. But the program taught me a lot of math concepts and tricks that other GMAT courses had not taught me.

On my first real GMAT attempt after doing TPP I got Q48 and then on my last try I ended up with Q50.

I would recommend the program anytime (I've already recommended it to a few friends). It is kind of expensive and a lot of work, but it definitely helped me.

P.S. Make sure you review each chapter multiple times. There is so much work that you can start forgetting things from early chapters if you don't review them.

P.P.S. I used two other GMAT courses before TTP (I ended up with Q45 after both of them) so I can't give TTP all of the credit but I will give them most of the credit for improving my quant score from 45 to 50.