I am working as an engineer in a Telco,California with 4yrs work ex. Studied for 1month amidst rigorous travel schedules and hectic lifestyle.
Took online training course under MGMAT. Fantastic course schedule and curriculum. All my MGMAT as well as GMATPrep tests
were consistently 680-690.
Got a headache on the test day which probably effected the score.
In One sentence for all those aspiring for GMAT, Concentration is the key factor.
I had numerous reviews and debriefs on this site. I finally came to the conclusion that each and every induvidual's reading technique's are related to him/her. They cannot be applied to all. You are the best judge of your situation so come up with your own game plan.