Haven't received my score yet, only tested a week or so ago. But I'd say your hierarchy should be coursework > text (medium robbins, or Goljan RR) >>> FA > Q banks.
coursework, coursework, coursework... Should be your #1 priority, you should aim for >2 SDs above class mean on your exams. This is absolutely critical to making your dedicated study time efficient. You can get though all of first aid in 3-4 weeks, and have a ton if it stick if you've worked hard during MS 2, regardless of how closely your school teaches to the boards.
Speaking of not teaching to the boards, my school has some bizarre objection to acknowledging that the boards even exist. We had more reading assignments from NEJM than robbins or any other high yield primary text out there. It was annoying and frustrating at the time, but somehow it actually worked... What's more, I had a 8-10 questions on my exam that came exclusively from overtly clinical coursework (that I initially thought was completely irrelevant to step 1)... things that weren't in either Q bank or first aid. Point being: even if your school doesn't teach to the boards, you should still do your best to learn that **** cold. It may show up again and even if it doesn't, it contextualizes the material in FA and helps it stick during your study period.
That being said, if you had to go through FA along side courses, I'd argue its worth reviewing the basic science garbage. Immuno, micro, genetics, biochem, embryo, CLINICAL anatomy (eg blue boxes in Moores)... things which would dovetail nicely with the organ systems you're covering in lecture and PBL, but require some relatively focused studying/review.
Don't overdo it though, focus on your coursework first and foremost.