Hi LoneSurvivor,
Based on what you're asking, I assume that your concern is that you are looking for practice CATs that will give you a realistic assessment of your current skills (and that seeing questions on a CAT that you already know that answer to would make the results 'inflated' and unrealistic). Those ARE important concerns, but you don't have to restrict yourself to just the 6 Official GMAC CATs. Before I can offer you any 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) Which 'brands' of CATs have you used so far and how have you scored on EACH of your CATs (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your goal score?
5) When are you planning to take the GMAT?
6) When are you planning to apply to Business School?
7) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich