Well - for starters, I was on the same boat.
I scored a 710 on my GMAT - 50/37. What added to the quandry was - I was making consistent v40+ in all my practice tests.
I was in a terrible flux for well over a week on whether to re-take my G.
On reading through multiple forums / interacting with student adcoms and with a few popular consultant houses, I figured that GMAT is way OVERRATED than it actually is.
Typically adcoms spend a paltry 1-2 seconds to see whether you fall within the school's acceptable range [typically 80/80] . A balanced 700+ is more than sufficient to get you into the 'discussion' phase of any top tier school. From then on, its just your marketing handle and clarity that you manage to establish right across your entire application packet ranging from your resume to the essays ! your time/benefit ratio will be best justified if you work on your real determinant - your holistic app packet !
That being said, a high G 750+ can help you get away with some dough, not to mention a relatively favorable tilt from employers esp if you are targeting to break into the MC/IB world. Then again, a MBA from a top Bschool will obv help ur case in the forementioned industries.
At the end, its your call

G'luck.