Hi
RachitBandale,
720 on the old GMAT would translate to 665-675 in GMAT Focus according to the
Concordance Table. Your current mock scores are right above that range. And I'm assuming that you have not been 100% familiar with the new DI question types and sectional strategy yet. So it seems that there is indeed some room for improvement.
So yeah, I feel that OG should be your main prep resources now, as there is no better DI question banks out there than the OG, which is what you need the most. It's likely that your only gap now would be the new DI question types - G&T, MSR and TPA.
Most of the new DI question types (formerly IR question types), in my view, are just an overlay on Quant and Verbal skills, which you are already strong at. So the main thing you want to do is to familiarize yourself with way the questions are structured. Data Sufficiency questions are those used to be in the Quant section in old GMAT, but now with a more word-problem flavor and some new "logical DS" type of questions (some call it Verbal DS). These are also best practiced from the OG.
If you need, there is a GMAT Ninja DI playlist on GMAT Club Youtube channel that covers every question type in DI. May come in handy as an overview of strategy to each question type.
As for Quant and Verbal, I feel that you may be able to skip the Easy questions from OG and focus more on the Medium to Hard questions. If necessary, you can complement OG with some Hard questions from GMAT Club.
Just my two cents. Best of luck.
RachitBandale
Nope, I scored a 720 on the old GMAT (actual exam, 2 attempts). In the focus edition mocks, I scored around 675-685.