Having taking the MCAT yesterday, I'm going to weigh in on the side of EK- both the books and the audio osmosis. They are rather goofy, but I found that during the stress of the exam yesterday, I actually doubted myself in some of the easiest topics (i.e. what is sympathetic and parasympathetic). The only thing I remembered for sure was a stupid joke they used to differentiate the two, but I did remeber that and therefore got them right! Yeah, I got annoyed with all the sounds and bad jokes while I was studying, but I guess that kind of burned them into my brain...