My preference would be the first option, but I beg you not to make your decision based on this. It's one of the least important things I can think of. Pre-clinical studying these days is pretty much done at home using Pathoma and Anki and other commercially available resources. You will learn the material the same at both schools. The difference in Step 1 scores is far greater within any given school than between any two given schools, plus I think you'll be taking it P/F anyway.
Things that are all far more important:
- Cost
- Location
- Quality of affiliated hospitals
- Prestige/reputation
- Research infrastructure
- Quality of residency programs in IM and other core med school rotations
- Existence and quality of home department in any specific fields of interest
- Condensed pre-clinical (not an option for you I take it)
- P/F pre-clinical
From someone who has been through med school—in terms of importance, this falls just a step above the quality of sandwiches served on interview day.