If you feel you can improve your GMAT score by 40+ points, it may be worth taking the test again. The GMAT is a self-reported score, so MBA admissions will only focus on your highest test score. Thus, there isn't a downside to taking the test again. The only negative would be the cost and the time spent studying, however it appears like you are already scoring very well on your practice tests.
I hope this was of help.
Conrad and the Stacy Blackman
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