Nice job on improving your quant on that last test! (I know you want a higher score than that, but you're moving in the right direction - nice work!)
Can you remind me what you've been using so far?
Also, I won't necessarily agree that you need to move to all new material. There's a strong chance that you haven't yet learned everything you could have learned from your existing material - if that's the case, then the problem is inefficiency of study, and that problem will persist with new material. Better to make sure you're studying in the best way.
So, how are you studying? What does a typical study session look like? How do you review problems? How do you track your work?
What are your specific strengths and weaknesses? How is your timing?
Use the below to analyze your most recent MGMAT CAT:
http://www.manhattangmat.com/blog/index ... ice-tests/You also may want to read this:
http://www.manhattangmat.com/blog/index ... -the-gmat/