I'd say that I really approached first year of school not studying for step at all and I think most all of my classmates similarly. In second year, a chunk has probably begun to do some studying on the side(by that I mean either going through the basic comprehensive books(First Aid/Rapid Review) or doing questions). in first year, I kind of kept an eye on step material, maybe having looked through the sections like once or something but most of the studying was done straight out of the textbooks/research needed for the class.
If I were to say what'd I think would be a good approach out of the gate, I'd say focus on classes and if you want use review sources VERY lightly so you get a feeling but mainly use textbooks and learn it properly. At some point, probably not right away but when you've learned a fair amount, start doing questions if you feel that will help to get used to boards format. But aside from maybe using rapid review along the way to cover path, much attention probably doesn't need to be paid towards the review sources when you'll have everything you need and more in your curriculum to spend time on.
