let's all clarify this P/F stuff.
There are schools that are Pass/Fail, for a variable number of years. I don't know any respectable place that has Pass/Fail for clerkship years. Several schools just have Pass/Fail for the first year, some other, the first and second years. Indeed, programs track the progress of their students, and rumors go around about how you can score AOA points in the first two years even though it's technically P/F. I've seen a dean's letter from at least my institution, and it mentioned NOTHING about the first two years in terms of internal ranking.
If the dean's letter does include your class ranking from the first two years, even if it is a Pass/Fail institution, then it completely defeats the purpose of being Pass/Fail to begin with and you might as well go to a school that has grades. At least you won't have the pretense that you aren't being ranked. It's something that you should ask in your interviews, if you are that concerned.
If it's Pass/Fail, and there's no mention of pre-clinical scores in the dean's letter, than effectively, you all you REALLY have to worry about, is learning what you need to do well on the step 1.
Since there is such variability in how schools grade their first two years, this has caused a gravitation towards using USMLE step 1 scores as a criterion for filtering out students for competitive residency programs. Just as you apply to medical school now, you are realizing that GPA can be quite variable depending on what type of institution or discipline you are studying. (i.e. Crap University, Psych Major vs. MIT Nuclear Engineering). Hence, schools rely on MCAT's, quite a bit. This concept is even more accentuated in medical school, because you don't even have GPA's in the first place. (there are exceptions).
Pick your school wisely, and realize that no matter what people say, competition is intense, EVEN at pass/fail schools. It's a darwinian process, and those that got this far tend to be self-motivated, intelligent, and competitive.
I enjoy Pass/Fail, and i'm sure many others out there do as well.
If you go to a graded institution and are getting all Honors, all the power to you. I tip my hat.