Hi marrodcruz,
The most realistic CATs/mocks available are the 6 Official GMAC CATs. That having been said, there are a variety of different factors that can impact your score results, especially if you have seen any of the questions before (for example, is this the first time you took this CAT? Did you previously answer any of the questions from this CAT during your studies or did you see "clones" of these questions?) - in these cases, the CAT results would likely be 'inflated' and unrealistic. That having been said, if you took this CAT in a realistic fashion that matches-up with how you will take your Official GMAT then we should assume that the results are an accurate assessment of how you could perform on the Official GMAT.
While you might be tempted to take a lot of CATs during these last 12 days, it's worth noting that the process of taking (and reviewing) a CAT requires a significant amount of energy and effort - and takes time to 'recover' from. This is one of the reasons why you typically shouldn't take more than 1 CAT per week - and your last CAT should be taken about 1 week before Test Day. You could reasonably take 2 more CATs before March 18th, but you should not take any more than that.
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 in total? How many hours do you typically study each week?
2) What study materials have you used so far?
3) On what dates (or approximate 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 apply to Business School and what Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich