GMAT official Practice Question set bank is big/huge in numbers where else, GMAT club might have only those when someone had any doubt and needed an alternative solution methodology.
Still my feedback is GMAT club itself have big/huge quantity of question set covering most of the pattern, need to build concept, advisable is if, you are through with GC + latest OG + OG Advance, then only move ahead with addition MBA.com question set, that too only to test your skill, as one cannot test it on already attempted one.
I have MBA.com official Practice Question 1 & 2, quality of questions is Good specially for 700-800 range, this question surely test multiple concepts by single question, in my view DS, SC and RC are better than OG in MBA.com official Practice Question
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