There is no score that will guarantee an admission, let alone scholarship, at any school. With a 710 you are competitive at almost any top US school (baring maybe the top 3 H/W/S). UMD is a good school and I believe you are above their average GMAT. As soon as you hit the average mark for any school, you should stop thinking about GMAT. Keep in mind a GMAT score will rarely get you in a school but can keep you out if it is low. So as long as you have a score above the average of the school you should be fine. I think only 3-4 US schools have an average GMAT score above 710 and maybe 1-2 above 720. So you can virtually apply to any school confidently.