Hi lacaca,
While the 12th Edition of the Official Guide is an older book, most of the material is still relevant - meaning that the concepts, patterns, Tactics, etc. that you would need to handle the questions in that book are the same general knowledge and skills that you will need for the current iteration of the Official GMAT.
In your post, you stated that your Test Date was February 22nd (which is a little over 1 week from now), but it's not clear how 'ready' you feel to take the GMAT. If you are not close to your Goal Score yet, then you still have time to push back your Test Date.
1) How have you scored on EACH of your CATs/mocks (including the Quant and Verbal Scaled Scores for EACH)?
2) What is your Goal Score?
GMAT assassins aren't born, they're made,
Rich