Hi all,
To recap for the OP, for a student that has scored a 680, you will probably find the first few weeks of class to be easing in as you solidify the fundamentals and work into the more challenging material. You'll find the problem sets will get progressively harder both as you progress through the class and as your performance proves a high level of mastery. And don't forget, when you get to those more difficult problems later in the course, you can use our academic email support and attend office hours to get that teacher feedback to make sure you're on top of things.
As far as the difficulty of questions goes,
MGMAT is well-known for having a plethora for very challenging questions, particularly in quant. The problem is that questions that go out of their way to introduce complexity do more disservice than they are worth because they are untestlike. Standardized tests are all about pattern identification, and working with practice items that are only loosely correlated with the official exam will not yield results for most students on test day. It is, to be frank, a dangerous way to study.
Also, keep in mind that often the strangely difficult items that can sometimes be found on the GMAT represent the experimental questions that ACT and GMAC play around with for psychometric uses.
Lastly, to respond to Caitlin's post. We're friends with
MGMAT in general and appreciate what they've done to raise the bar for GMAT prep in the last ten or so years. However, Knewton gives more than practice problems. We have literally hundreds of learning objects and videos to go along with thousands of practice questions. Not only that, we're not going to charge you $300 to take a course again if you haven't yet seen the results you wanted. Knewton gives you a full year of membership, so you can take as many classes as you see fit until you are comfortable. We also offer a 50-point guarantee, while
MGMAT doesn't even offer the 10-point guarantee of it's new parent company, Kaplan. We strive for the best product with the ultimate in convenience, and we stand behind it.
Hopefully helpful,
Josh