What should I use to study for Step 1

Hey! I was wondering what prep books people are finding the most beneficial for USMLE step 1? I know of Kaplan's, and First Aid's but I was wondering if one is necessarily better than the other, or if there is a 3rd option that tops them both? Thanks
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Tags: Medical Students - MD Source Type: forums