Agreed - it depends on the subject. If you want more than just "review":
Biochem? Lippincott.
Cell/Molecular? HY is sufficient.
Neuro? HY is sufficient.
Embryo? Langman's.
Physio? BRS, BRS, BRS x 1000.
Micro? Clinical micro made ridic simple.
Immuno? That little book by abbas is simply wonderful.
Behavioral sci/epid? HY is sufficient.
Pharm? Pharmcards are probably sufficient; supplement with Lippincott or Katzung PRN.
Path: read goljan's RR from cover-to-cover a few times. Supplement with Robbins if you really need it.
Make sure you exhaust a QBank - I recommend USMLEWorld. Buy FA and annotate like it's your j-o-b.
This was my reading/to do list for Step 1. In retrospect I wish I had spent more time with CMMRS and HY neuro - I ran out of time towards the end and didn't really spend enough time on these 2 subjects. To be totally honest, I didn't completely exhaust my UW questions, either. But I had the same concerns as you - there was some stuff that I never covered during 1st or 2nd year on step 1, and even more stuff that I'd only seen once and/or wasn't comfortable with. So, I read more than just review books - I actually went back and read some heavier material.
It took a little longer to slog through the reading, and my days were pretty miserable for about 6 weeks, but doing the reading, annotating FA, and then backing it up with UW questions really helped solidify the material in my head. And once I had finished a topic (which included reading text/review book, annotating/FA, and exhausting the Qs on a subject in my qbank), I didn't need to go back and look at it again; I just moved on to the next subject.
This method probably isn't good for everyone, but it worked out for me. I passed Step 1 and I never have to take it again. 🙂