MGMAT's Online Course with Josh Braslow is the way to go

I'd highly recommend Manhattan Prep, and specifically Josh Braslow as an instructor. When I was initially looking up who to take the course with, there were many highly rated instructors. Josh's name obviously came up, given how long he's been at MGMAT and his consistently strong track record. Despite the fact that there were some younger instructors who were highly rated, I figured that Josh's experience with the test for many years would be helpful. And boy, was I right! Josh really understands the test inside out, and will help you understand how the test writers think about questions. This goes a long way in terms of understanding guessing and elimination strategies. Josh also has a great sense of humor, which make the classes very enjoyable - making it a lot easier to sit through classes starting at 7am!

I also had a post-course assessment with Josh, which I would HIGHLY recommend signing up for ASAP after the course ends, provided that you were able to keep up with all the classroom requirements. I had one month between when the class ended and when I was taking my exam, and spending about 45 minutes with Josh on the phone really helped me develop a plan to elevate my performance in the last 4 weeks before my exam. We analyzed my prior performances on practice exams, focused on key areas, and made sure I was spending my last few weeks efficiently.

The first time I looked at anything GMAT-related was in February 2017. I improved 140 points from my first practice test in February 2017 (620) to my actual test in May 2017 (760) - all in the span of 3 months

It's not about working hard and doing as many practice questions / tests as you physically can, it's about working smart and using your time efficiently. Josh and MGMAT do a fantastic job of reinforcing these principles.