Hi,
I was wondering if it's okey to prepare for GMAT without the official guide. I'm aiming for a high score, so is it okey to do without the guide. I have Cliff's GMAT CAT guide. I found Cliff's pretty good for TOEFL. Is this book standard? Also, i have the arco guide for AWA. I read on one of the posts that, this book isn't very reliable? If so, what would you suggest for essays. How can i grade my essays? Is there any good free software for this? Should i refer to Kaplan also?