Just wrote the exam about a week ago, and yes there is stuff on the exam that isn't in first aid or uworld. But let's step back for a moment here. To be quite honest, about 90% of the content of the step 1 can be learned either directly from UFAP (Uworld + FA + Pathoma), or can be derived from information learned in UFAP using critical thinking and logic. You can absolutely score a 250 using only UFAP (not everyone, but some people certainly can. There is an element of inherent intelligence/critical thinking ability involved as well obviously) However, the other ~10% of questions are not going to be found in these resources, and you don't know where these additional questions are going to be pulled from or of what topic they will be on. So there is definitely a logarithmic scale with diminishing returns in terms of return-on-investment on time spent studying additional resources beyond the core materials in an attempt to cross that lucrative 260 mark. You could spend 1000 hours studying UFAP and get a 252, and to get bumped up 8 points to a 260 you would likely have to spend an additional 1000+ hours of study on other relatively low yield materials in the odd chance that you will cover some of the minutiae that is selected for your version of the step 1. Worth it? For most people probably not. The difference between a 252 and a 262 applicant is fairly negligible to most programs, and factors like reference letters, research and interpersonal/interview skills will usually be weighted more heavily than a step 1 score being a few points higher for applicants who are already scoring 250+ anyways.
