by StaceyKoprince Tue Sep 30, 2008 3:55 pm
Haven't heard of the website you posted, so can't comment about that - sorry!
Generally speaking, if you have finished OG but don't yet have the score you want, then you aren't done with OG because you didn't learn what you could've / should've learned from the official questions. Getting better is not just about doing lots of new questions all the time - getting better involves actively studying / analyzing problems after you do them. I can easily spend two to four times as long analyzing a problem as I spent doing it in the first place.
Also, when I say "analyzing," I'm not talking about looking at the solution and making sure you understand it. You should do that, of course, but that's not analyzing. Analyzing includes things like: hmm, I made a mistake - what mistake did I make and WHY did I make it? what could I do to minimize the chances of making the same kind of mistake in the future? Or: I got it right, but did I do the problem in the most efficient way or is there a different way to do it that would've been easier / faster for me? Or: what are the traps or tempting answers here? (especially in verbal) Why are they traps / tempting, and how can I avoid them anyway? Or: how could I make an educated guess on problems of this type (and this is easier to learn on problems you got right - then apply the lessons to harder problems of the same type)? Or: what are the clues in the wording or setup of this problem that let me know what type it is or what I should be trying to do to answer it? Or: how will I recognize a problem of a similar type in future? And so on.
At the end of the day, the best questions are the official ones. You've got the 1,400 questions in the three current OG books. You could also get OG 10th edition, which mostly overlaps with OG11, but about 25% of the questions in OG10 are different, so that's another several hundred questions. You can also buy GMAT Focus for additional quant questions. You've also got 2 clean (no repeats) GMATPrep tests plus you can keep taking the test afterward to pull out additional questions. We're now approaching maybe 2,000 questions (though granted that some subset is well below the level you're trying to score). Even so, that should be plenty if you're studying in the right way and really extracting everything you can out of every problem!
Stacey Koprince
Instructor
Director, Content & Curriculum
ManhattanPrep