Hi Andrew -
Thanks for your inquiry. The best time to submit your application is when you can do a high quality job on it - a high quality R2 application is better than a rush R1 one, in other words. That being said, there is generally a slight (but only slight) advantage to applying in R1 simply because fewer applicants tend to apply then which boosts a candidate's odds a little bit. So you have to weight the 720 vs possible 750 against the slightly better R1 vs R2 (assuming that this close to the deadline you still have time to do an excellent job on your essays and the rest of your application).
For the most part, there's not a significant difference for the schools between a 720 and 750, especially once the V/Q breakdown are both over 80%. A score over 700 and with 80%/80% is what most people strive for.
So you'll have to decide for yourself whether you can do a great job on the application now, and then weight the GMAT score vs the Round. My recommendation would be to apply in R1 if you believe you'll do a good job on the application, but I don't think it will hurt you to wait for R2 with a higher GMAT either.
Best of luck
Jessica Shklar
mbaMission
Our blog:
www.mbamission.com/blog