GMAT - way to go about

Dear fellow members, did take the GMAT around 2005 and scored a 620. Want to give it a shot again. At that time, I did Kaplans, registered for their course in Mumbai. It was good. But now, I can devote 2 hrs a day… Am surely looking at a 700 + . …

Dear fellow members, did take the GMAT around 2005 and scored a 620. Want to give it a shot again. At that time, I did Kaplans, registered for their course in Mumbai. It was good. But now, I can devote 2 hrs a day.. Am surely looking at a 700 + . Which are the best books / institutes in Mumbai offering GMAT coaching at present ? Do the courses really help ?