Dude 610 on your first test and that too on MGMAT is not bad. But I am concerned with amount of time you have to appear for mock tests and most imp. post test analysis. I assume you will also spend at least some time on theory. Regarding the material, I too had brought Aristotle grail and other stuff but trust me, Manhattan strategy guides are all that you need. Sufficient and enough. In addition do have a look at some video sessions from Ron Purwal of manhattan. These videos are available for free on manhattan website. Also if you get time do have a look at OG 13 You can also order for additional GMAT Prep questions for $29 from GMAC website. That's all..you are set. All the best.

Ameya

Thanks Ameya for the suggestion. I can spare daily around 3 hrs on weekdays and 6-7 hourson weekends for the prep.

Brief anout my profile:

Have rich Industry experience of 12years and currently working with one of the Big4 consulting firms [good part is Education has no age or experience bar!!!!!]. A Mechanical Engr. by education hence Quant is a bit OK but still have to work a lot. Looks like will have to put in considerable time and effort on Verbal.

Thanks and Regards

Nayan4GMAT