Per the GMAT, you want to aim as high as possible (obviously). If you're gearing for the top 5 b-schools, you'd want to aim for at least a 700, ideally 740+. If you're going for the bottom of the food chain (USC, Johnson, Tepper, etc.), a 680 will put you at the ballpark. Age-wise, you're on the older side of the dotted line when it comes to Harvard and Stanford, as these two schools prefer younger candidates. However, if you're going to apply to a range of schools (Harvard, Columbia, Darden, Johnson, USC), you should be able to get in at least one of them. My recommendation is to apply this year and don't wait anymore. You're dangling on the sideline of a FT MBA and an EMBA if you wait just a couple more years.
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