I have been practicing with the Official Guide, and I usually get 8 correct answers out of 10. However, when I practice with the "1000 SC questions", I obtain 6 out of 10 :s
Which is the set of questions more real? Maybe the 1000 SC questions are more difficult than the real exam, and I don't want to waste that time that I could use in another part of the exam.
OG, logically speaking, is the best study guide. However, questions on the real gmat are harder than the guides.