Hi Karthik,
If you think you need a score 700+ for your goals, what ever they may be. For scholar ship or schools that you are interested. Go a head take. People have done that and achieved the scores they wanted. But you need to sit back analyze a bit what is needed for you get the score. There is very little info in your post on what you have studied or how much effort you put for your 3rd attempt. Understand your weak points and work on it. I have seen people getting verbal 37-38 range. Going to 40+ may be some leap.
I think the following two points about GMAT exam are very important.
1. I have read a statement from GMAC that GMAT scores have absolute meaning in the sense a score of 600, 10 yrs ago is same as 600 today. Only percentile may change, i.e. number of people crossing 600 may change. What does it mean? It always tests the same concepts but may be with a little twist not much at each level. I also think because of these graded levels, you score also goes in steps.
2. GMAT prep is a acurate estimator of the score. How is it doing? It goes back to 1. It is testing the same concepts again and again. So I think write a GMAT prep test and analyze each problem. See what is the previous problem and next problem. There is a pattern. Also, see each question what is it testing. (I have taken a MGMAT test, they very closely mimic GMAT prep). Prepare each level questions.
For example when I took GMAT prep analyzed the following for SC:
It tested a modifier question "Like X, Y"; Next level down the line it tested "like X's, Y's" ( with possesives ).
similary for subject-verb. So when you do OG-questions assign the question to a concept and you know next time when you make a mistake you understand that you are making a mistake and your brian detecting that pattern. train for it.
One more thing when I gave MGMAT test, I analyzed the CR questions, I got all 700+ wrong. I answered them when I don't have a time limit after the test. What does it mean my brain is not trained enough for deep thinking under pressure.
By the I haven't given my GMAT, but that these would be useful for you if you decided to take it again.