Hi zmzm,
Many Test Takers become too fixated on the 'implied level' of the questions that they're working on - instead of what really matters: defining WHY they're getting questions wrong and becoming more efficient at approaching the overall Exam. It's also worth noting that just because a 3rd party describes a question as "650 level" does not necessarily make it so.
Since you're clearly looking to improve your GMAT Score, then some changes to your current studies are probably warranted. Before we can discuss how best for you to proceed, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) How long have you studied?
2) What study materials have you used so far?
3) How have you scored on EACH of your CATs (including the Quant and Verbal Scaled Scores for EACH)?
4) Have you taken the Official GMAT before (and if you did, then how did you score?)?
Goals:
5) What is your overall goal score?
6) When are you planning to take the GMAT?
7) When are you planning to apply to Business School?
8) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich