I'm taking the Physics C exam, along with CS AB, Calc BC, US Govt, and AP Lit. As for the Physics one, as said before, the multiple choice is concepts. but there are some calculations, and some questions are, where did this come from? there were some questions on some practice tests that take 10 min to do. no one could figure them out, and when my teacher told us, we were like, those questions should be skipped. the overall test isn't so bad though. the free response, as said before, is kindof nice with points. write things down, i.e. conservation of momentum, conservation of energy, etc. etc. they'll usually give you a point for just saying Ei = Ef, or Pi = Pf, etc. depending how they decide to grade it.
best of luck with the exams for those taking them!