And about how to work,
please and please don't study veritas, they're no different than rubbish, i am a non-native speaker but i found wrong answers on their free "CAT" exam. I esspecially mentioned CAT, because a CAT is adaptive, when you do right it should get harder. But even though i did a lot of correct in the 30th question they asked me something about simple aritmetic!
For verbal part official guides including 10 are perfect. They are invaluable. But for quantitive, esspecially if you are an engineer and did well in calculus in university, they are useless. I cant say for sure but the questions are like you will see when you get 30-38points.
Because of OG quantitive i got 550 on my first attempt! I am really angry about that still! The questions were so easy that i felt that i had to spend no time to study and thought there were no hard questions in GMAT quantitive. And in the exam when i was stucked at one question, i though that would be the only one so spent nearly more than 6 minutes:) Guess what i couldnt have time to do last 5 questions so i had to guess them.
I have never used material like Arco, Princeton Review so i cant say anything bad about them but i dont believe any other material could be helpful except OGs in verbal part but i still insist dont waste anytime in OGs quantitive if you are already stong at quantitive.
So what to study for q? There are many sites for that, i bought a couple of questions and they were much better than i expected. You can also find something from the materials needed for the exam of the entry to university, here in Turkey, the competition to entering university is extremely hard but i dont know it for everyone's country whether they have an entry exam to university.
Dont expect miracles! When i first took GMAT i said my mathematics is good my english is good so i should get a superb score and didnt study well, and then was shocked in the test center to see 550:) At my second attempt i took more seriously and took 640, with 50 quantitive 95th percentile. My aim was to raise it to 51 and 99th percentile but dont know what went wrong maybe i did some basic miscalculations (i often do that:) but was a bit said to see 49 because it was lower and if i could have risen for only 1 point i would get maybe 730 maybe 740 i don't know.
Good luck everyone!
