A couple of points I want to make here. 1. UW is insanely hard. Many have told me UW is about the same level as the real Step I. It isn't. I've done the 100 sample questions from NBME site, where are the ONLY "official" Step I questions we can obtain. They are significantly easier, straightforward, not-testing-OMGGOTYA-trivia. 2. I'm studying with Micro Made Ridiculously Simply, BRS Path, and K&T Pharm. I memorize them all. I do the practice questions after each chapter and do extremely well. I use FA too, but after reading those books FA is a a joke. When I switched to UW, I got kicked in my ass. I score around 55%-60%. Hitting 70% sometimes. 3. I know many people are studying with only First Aid and UW. I don't know how they can do that. For those people, 7 out of 10 questions on UW you would have to make a hopefully educated guess. There's a HUGE gap between the coverage of FA and UW, which is perhaps several detailed review books and some real-life practice experience.