Thanks man! To answer your question, if your school administers the NBME CBSE then you can use that as a baseline. I thought this test was strikingly similar to the real deal in terms of ambiguity, difficulty, and question style. NBME 11 or NBME 12 can also serve as adequate baseline measures of performance.
Starting day one of medical school I worked very hard to build a strong foundation through textbooks and course material. Through systematic repetition over the past 2 years I was able to maintain and fine-tune this foundation. I attribute my success on step 1 almost entirely to the knowledge base that I developed during MS1/MS2, and not to my dedicated step study time. Unfortunately, I can't accurately answer your question because I never felt that way.
As general advice to those students who months or years from now read through this thread and come across this post: if your goal is to hit 260+ on USMLE step 1, I suggest you give yourself the best odds for attaining this goal by working incredibly hard during MS1/MS2. You will never be given a definitive guarantee that you will break 260 on the real deal. There are too many determining factors (e.g. MS1/MS2 performance, test day performance, individual skill and test-taking ability, exam form difficulty, etc.) contributing to this final score for there to be any absolute certainties. All you can do is give yourself the closest odds to a guarantee by always giving your best effort. This does not start the first day of dedicated, this starts the first day of medical school.
