USMLE Step 1
General

There are quite a few comprehensive reviews. Since they try to
summarize a large volume of information they become rather
sketchy and not so useful. The only one that I found worth reading
is First Aid for USMLE Step1.

In terms of question materials I used:

NMS Review for USMLE Step 1: useful, but the questions tend
to be more difficult: I scored only 80% in those tests.

Body Systems Reviews: again, useful for studying, but don't use
them to auto-evaluate your progress- they are rather difficult.

Kaplan Step 1 QBank: purchase the 1-month online access to
Step1 Q bank, close to your test date. It contains very-good quality
questions. You can take mock exams and monitor your progress as
well.

The practice test that USMLE provides is the most accurate
predictor of success. Take the test about one month before your
Step1. If you give the correct answer to at least 90% of the
questions, you have a good chance of scoring above 95 in the real
test. This was true for me and many of my friends.