Kaplan continues to remain a top choice among people who are taking exams. There was recent poll on Reddit which indicated that they were the favorite choice for the series 7 exam. I like Kaplan a lot but I will say that they should improve the video side of their business.
Kaplan's textbook is good but their edge is in their qbank. They are the only prep provider to sell a qbank as a stand alone product and it is highly customizable. I assume that other prep providers could make their questions a stand alone product but none of the major ones have done it. STC sells supplemental exams but you only get about 500 questions. With Kaplan, you can take full length exams or take quizzes on certain topics. In addition, you can refine exams to questions not answered previously and/or answered incorrectly. I usually recommend taking exams the qbank instead of the simulated ones because with the simulated ones, you will end of getting repeat questions.
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