Trying to get the your highest scores in both sections is like chasing a dream. The problem is that you spread yourself thin when you try to prepare your hardest for both. You've truly showed that you've mastered both Quant and Verbal, but it is always going to be tough to get your highest on test day. A Q50, V38 is an EXCELLENT Score, especially with that Q50. What is that? A 720? 730? I think that spending anymore time on the GMAT might show that your concentraiting on the wrong areas. Trying to grab a few extra points when you're already at or above average just shows that you're putting emphasis on the wrong areas. The GMAT is just one of many parts of your application. I know it can be tough to leave points behind, I for one was averaging Q50, V40, and def left some points in quant. But the time and effort necessary to improve just didn't make sense. 760s get rejected all the time, 680s make it in all the time, its all about the rest of your profile. I would advise not retaking unless you are 100% sure you can increase your score by 30-40 points, without this, I believe you'd be wasting your time that you could be spending on your app. The difference between a 720 and a 750 are minimal at best. Adcoms are gooing to check off the "Solid GMAT - Solid Quant" check box and then move onto the rest of your app. If you need any further proof, look at this calling all aplicants page for your desired schools: calling-all-darden-fall-2012-applicants-116617.html
Look at the graph with the dots on it, and find the red ones. Those are people that were rejected and many had huge GMATs. You've got to bring it on the rest of your profile, and it might be time to concentrate your time elsewhere. Good luck! and let us know what you decide.
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