Hi sunkyukim,
While the Scoring Algorithm on the Official GMAT takes into account a number of different factors, the amount of time that you spend answering a question is NOT one of them. Most GMAT questions are written so that they can be solved in more than one way though, so in an informal way, the GMAT does 'reward' you for being efficient, being a strong pattern-matcher and avoiding long, overly-technical approaches (when faster options are available). If you can answer a question in less time, then you will have more time for all of the remaining questions. Since many GMATers have pacing issues in the Quant section, the Verbal section, or both, there's certainly an incentive to becoming a strong strategic and critical thinker for this Exam.
Before I can offer you any additional advice for your studies, 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) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your overall goal score?
5) When are you planning to take the GMAT?
6) When are you planning to apply to Business School and what Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich