Yesterday, I took the GMAT. Unfortunately, I didn't do too well 590 (Q38 V33), but I'm determined to improve my score. I think I have the basics down, but I need to improve on some minor weakness and time management issues. Therefore, I'm planning on taking either the Manhattan GMAT online or the Knewton GMAT Prep. I want to write the GMAT again in 4 weeks. Does anyone have any suggestions on which would be a better course?