Hello,
lacazet2k. (No relation to the Arsenal striker, I take it?) If you need a bunch of high-quality practice questions, why not try either an online learning module or a GMAT Club subscription, with all that that gives you access to? Regarding the former, there are several options for Quant that are quite reasonably priced--Math Revolution, EMPOWERgmat, or
Target Test Prep, for instance--even if money is not so much of an issue. The benefit of online, module-based learning is that you can target specific areas and track your progression in each. It saves a lot of the tracking work you do personally if you work through books exclusively, and many students make quicker gains. As for the latter, a GMAT Club subscription, many 50-51 Quant test-takers have vouched for the high quality of the Quant questions on offer, with some of these members saying (in their debriefs) that the GMAT Club questions proved harder than those on the real test. Again, if money is not a consideration, then why not go with material that so many other high-scoring candidates have vouched for?
If you are more of a book learner, something I can relate to, you should at least check out the official publication
GMAT™ Official Advanced Questions. Although Verbal questions are also included, many of these tough questions are unique to this source. You might also check out the
Manhattan Prep book
GMAT Advanced Quant. I am assuming
the harder the better from your original post indicates that you are ready to take on advanced material. If not, you can look for other, less advanced guides, but I think that between what I have recommended above and the material you already possess, you will have more than enough to hit the highest score you can.
Good luck with your studies.
- Andrew