Most interviewers are good at NJMS and relaxed. If you get James Hill PhD, you should be cautious. He's very nice, but he gets into your head, asking various very tough scenarios and asks you how you'd "tick", knowing yourself. Pretty tough scenarios, if you ask me.
Michael Katz is the financial aid head... he's very nice and relaxed. Just wants to know you more.
C.R. Spillert, PhD is another nice guy. Know about HMO/PPO, Medicare/Medicaid, etc. He'll ask you about those.
Sometimes, Mr. Lonnie Wright does interviews (I think)... he's very nice and relaxed. Just converses with you basically.
I think that they want to hear you think out-loud and react in a main-stream way, at the same time be able to think from all different angles of a tough situation. Also, know about yourself and reasons for being a doctor and not some other field in healthcare like nursing/pharmacy/tech/etc.