my college, attendance is required. but then again, much smaller class then 200 students. But at the same time i do think that having to go to class every day makes your educational experience just a bit better. but then again i am very partial.
if you approached the AP courses the way you were supposed to, then yes the AP courses are simulation of whats to come. I have found that the AP, whether or not i got credit for them, were very helpful in preparing me for school. Plus AP Physics and AP Chemistry, made the college level chemistry and physics easier, and i was able to learn even more in those subjects, gave me a nice advantage over other students! If you think about it, AP exams are usually the same week as regular college final exams. So the pace is just about the same as well.