Hi jotce,
First off, both a 680 and 690 are strong Scores, so either could be enough to get you into your first-choice School. That having been said, your Quant Scaled Scores might be seen as a 'red flag' at certain Programs. Many Business Schools view an Applicant's Quant Scaled Score as an indicator of how that Applicant might handle the 'academic side' of the Program - and a Quant Score in the low-Q40s won't impress anyone. That score implies that you did okay on many of the "math" questions that you saw on Test Day, but you made a number of little mistakes throughout the section and you missed out on LOTS of 'strategy-based' points. This is meant to say that by focusing on Quant Tactics, you'll be better able to increase your GMAT Score AND better impress how Business School Admissions Officers will view your potential to handle their respective Programs.
Since you have a specific School in mind, you would likely find it beneficial to speak with an Admissions Expert about your overall profile and plans. Those Experts should be able to answer your Admissions questions and help define the specific areas of your profile that could use some improvement.
There's a Forum full of those Experts here:
https://gmatclub.com/forum/ask-admissio ... tants-124/If you do choose to retest, before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
1) How long have you studied in total? How many hours do you typically study each week?
2) What study materials have you used over the course of ALL of your studies?
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)?
You might also choose to purchase the Enhanced Score Report for your most recent attempt. While the ESR doesn’t provide a lot of information, there are usually a few data points that we can use to define what went wrong on Test Day (and what you should work on to score higher). If you purchase the ESR, then I'll be happy to analyze it for you.
GMAT assassins aren't born, they're made,
Rich