Hi there Clicks,
My impression of the highest-level Quant questions on the GMAT was that they required a reasonably strong familiarity with the quantitative concepts tested. I'm not sure about the exact variety of questions available in the
MGMAT books, but it seems to me that it may not be the most effective - or, at least, efficient - approach to simply try to run your way through the entire stack in hope of being prepared for the same types of questions on the actual GMAT.
Rather, it might be better to just reinforce your grasp of the basic concepts relevant to the GMAT, and develop your facility with them to a point where you can apply them in a wide variety of situations. The
MGMAT questions which you have might come in handy here, but you'll have to make sure that when you try them out and check your responses against the suggested answers, you understand exactly why it is you were correct/wrong.
Hope this helps, and best of luck with your next GMAT!
- MrFong