I agree with Z, but want to add a bit. It is definitely true that AAMC exams give the best approximation, but PR exam scores need to be reasonable if you hope to have a good real MCAT score. I have seen mid-20 scores become 30+ on the actual MCAT many times.
But scoring below 20 on two consecutive exams might be cause for a small concern at this stage. Take an AAMC exam SOON and see how you do. If you are in the low 20s, you might want to figure out what the difficulty is before you sit for the actual MCAT. You can defer it until April for a small fee.
One difficulty might be adjusting to the style of the MCAT, which can be corrected if you take a whole bunch of passages. Before you make any decision, you need to determine if your score is low because of informational gaps or faulty test-taking logic.
Being that you are in Davis, you are lucky in one sense (more than just two MCAT prep choices). Call the Berkeley Review and tell them you are interested in their course and that you'd like to sit in on a couple classes to evaluate their teachers. The classes review material in conjunction with strategy and analytical reasoning. Even if they only let you sit for two or three classes, I'm pretty sure those classes will help greatly. Hopefully they change your perspective on the test and provide a new way of thinking about the subject.
Good luck with your efforts. By the way, I PMed you a while ago.
Well, any input would help.
