If you are confident, that you can make it on your own than well and good. But if you lack the discipline to study it's better to take a review course. There are many good books that one can use to prepare successfully for step 1. Taking Kaplan is no garauntee for high score, you pay huge amount of money for the information that they are providing you to read ultimately you have to sit and read. Any way, good luck for the step 1.
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