Why limit yourself to those two options? I would consider studying on your own and using some of the materials described in these forums, like the Manhattan GMAT SC Guide, Powerscore CR Bible, OG, Manhattan GMAT Math books, etc.

Hi veggiedelite,

I'm one of the Grockit tutors, so I can tell you a little bit about how Grockit works.

Grockit starts at $29.99/month for the premium membership and optional private Tutoring Packages start at $50/hour. So you can work solo, in group games, then set up private or group tutoring sessions with one of the tutors to review your skill areas, identify weaknesses and work with on specific areas you'd like to target.

As you do questions on Grockit, your profile and "skill data" is built up, so you can see your percentage correct/incorrect for any question-type or skill tag. You can then make custom games to target specific weaknesses.

The premium membership also comes with Diagnostics and challenges, which provide Grockit percentile rankings that may be correlated to section-specific score ranges on the actual exam. GMAT & GRE students receive score predictions after completing each full-length CAT exam. As more users take diagnostics, challenges or CATs, our score prediction becomes more accurate. Our prediction is based on a similar algorithm to the one used on the GMAT, which is based on the number of questions of a certain difficulty answered correctly. You can find this on your skill data page as well.

Let me know if you have any questions -- Grockit offers a free 3-day trial membership if you wanna check it out!

You can also find answers to the most common Grockit questions here: https://grockit.com/blog/main/frequently ... questions/