GMAT Strategy

Hi GMAT course experts,

I am an Indian engineer with a 710 (Q49 V37) GMAT. I plan to retake the GMAT. Needless to say that I am targeting somewhere close to 99 percentile. Need suggestions on which online prep course would be the "right" one? I am not a beginner. I have studied for 4 months before taking the test but this is all I could manage.
I see few companies offer score improvement guarantees. Do these guarantees hold true when your first GMAT is 710?

Regards,
Vishwa

This is from the Veritas Prep website:

"The Veritas Prep Guarantee is a simple one: You may retake your Veritas Prep GMAT course, for any reason, free of charge within 12 months of the course start date. Even if you score a 710, but feel that with more preparation you could score a 760... retake the course for free. If you have taken the official GMAT prior to the Veritas Prep course and your score doesn't go up, you get your money back. No hassle. No risk. No questions asked."

Funny that they specifically use 710 in the example!