Just wrote this test yesterday.
Main resources: Case Files, FA, Uworld, Qbook. I also supplemented a little w/ Boards and Wards, CCS pocketbooks, and Deja Review Step2. Looked at A&L, and Pretest and opted to not use them.
Obviously I haven't gotten a grade yet. Our school just requires us to pass the shelf and I feel reasonably confident I did.
I felt the resources above were plenty of preparation. As others have mentioned on here, the questions on this test are very long - each one is a dense paragraph of maybe ten or more sentences. IMO, time management was probably the most challenging aspect of the test, and none of the question sources out there really reflect this. Even though you might have all the knowledge you need, most questions required you to filter a lot of extraneous and sometimes confusing info to get to the point where you could apply what you know to the question.
I suggest underlining the important details as you skim the paragraph - how many months the sx have been occurring, type of sx, etc as you go through the question so you can quickly refer back if you need to. Also, be prepared for questions to give you multiple timelines - ie this event happened 4 months ago, but this sx started 2 months ago, etc. so make sure you are focusing on the right timeline when you answer a question.
I also suggest marking questions on the test that: 1)you think you nailed - don't even look back at these 2)wtf questions that you could spend all day on and will still end up guessing and 3)those questions that require a bit more time and thought - these are the ones to return to if you have the time. I knew I had to read fast, and I ended up with about 30 minutes to check my answers.
Don't ignore lab values. I had a couple questions that sure sounded psychiatric, but checking a lab value changed my answer.
As with step 1, there were lots of buzzwords on this test, but due to other info in the questions, they often didn't match up to their buzzword answer. Read fast, but beware of jumping on the obvious answer.
Many thanks to all who provided advice on this test.