I used the Kaplan course online (i didn't do the classroom sessions bc i thought i could do it on my own), topscore, and my notes from my histology class (which i highly reccomend anyone take before the dat bc it helps tons!) The chem section was very conceptual, the bio section was a little harder than i expected and kaplan is def not in depth enough. the ochem section was about what i expected and kaplan was thorough enough. i was actually really surprised by my pat score but i kicked those angles' butts!