Hi 123456aswe,
First off, both your 680 and 700 are fantastic scores (they're both a bit below the 90th percentile overall), so either could be enough to get you into your first-choice School. As such, a retest might not be necessary. Since many Schools place a premium on the Quant Scaled Score, you might be better off submitting the 680/Q48 with your applications. Depending on the Schools that you plan to apply to, you would likely find it beneficial to speak with an Admissions Expert about your overall profile. There's a Forum full of them here:
ask-admission-consultants-124/1) When are you planning to apply to Business School?
2) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich