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I have nearly completed MGMAT CR 4th ed strategy guide except the minor questions chapter, but I don't feel confident after solving OG questions. My success rate for OG CR questions has been 50%, and my timing has not been great too. This kind of worries me as it clearly shows that I'm not able to efficiently apply the techniques mentioned in MGMAT CR strategy guide. I did not race through the CR chapters during the initial study phase. I just found the level of OG CR questions higher than MGMAT CR problem sets. As far as my timing is concerned, I believe I spend too much time analyzing the argument and writing down notes.

Is it worth reviewing Powerscore CR bible? As far as time is concerned, I can give another 2 weeks to review the Powerscore CR bible.

Please suggest if I should give Powerscore CR bible a shot or spend more time AGAIN reviewing my mistakes in OG questions?