Hi Ashish,
The content in the OG2016 is still useful, so you do not necessarily "need" a more recent version of the
OG for your studies. If you are looking for some new Official questions though, then one of the more recent OGs would provide that content. It is worth noting that while the
OG books are great sources for practice questions, they're not designed to teach you Tactics, patterns or the little 'secrets' behind the GMAT - for those, you'll need Course-oriented materials.
From your post history, it appears that you've been studying for some time (possibly over the last year). Before I can offer you any additional advice for your studies, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) Have you been studying consistently over the last 12 months or did you take any "time off"? Over the last 3 months, how many hours did you typically study each week?
2) What study materials have you used besides the OG16? What “brands” of CATs/mocks have you used?
3) On what dates (or approximate dates) did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your overall goal score?
5) When are you planning to apply to Business School and what Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich