I took it 2 years ago, I'm finishing my MBA in May of this year.
It's a CAT (Computer Adaptive Test) so what that means is when you answer a question correctly, it will give you a harder question next. If you get that one right, it will give you an even harder question, and so on.
If you get a question wrong, it will give you an easier question next. The harder questions are worth more points.
It's EXTREMELY important that you get the first 7 or 8 questions correct to work your way up to the hard level questions worth a lot of points, so spend a lot of time on those questions. Don't make any stupid mistakes on those.
Also, timing is huge on this test, so you'll want to take as many practice exams as you can to get the timing down.
If you can afford the prep class from Kaplan or Princeton Review they are good.