@ Adil

Brother read carefully i mentioned clearly GRE big book contain 40% material that is of no use because of the pattern , difficult level and question types etc.For instance, Anolgy questions are not being administered in recent tests,but Big book contain such questions.Moreover, the number of Quadrant geometry Questions is much lower in the big book while now a days the ratio of questions on quadrant geometry increased manifold.

However,The questions in Big book are those that were used in real GRE test previously administrated to examinees. My point was that all other books contain a plethora of practice questions, but they are far easier or much difficult than the real test or content is of varied nature asked in real GRE.
in a nut shell, GRE big book is a better option for practicing test material if used actively and efficiently not passively and blindly. if someone go word by word it is obviously outdated.

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