I liked the BRS flash cards for micro, pharm, and path... they're short, sweet, and to the point. I did not like Lipincott's cards, because they had too much info on them - they were more like an outline than a flashcard.
I used MicroCards and thought they were great. I used 'em for both the course final and a little bit for Step 1, and rocked 'em both. They don't have all the bugs you'll run across so I wouldn't recommend them for a primary resource, but I thought they were a really good review aid.