Hi! I just took my PCAT on January 4th and scored a 96. Unlike the person above me, I would say that Dr. Collins is probably the ONLY thing you need for your PCAT! It's the only thing I used to study and I had a good amount of questions that were repeated on my actual PCAT from the Dr. Collins study guide! In case you're unfamiliar, the study guide comes with packets of information for bio, chem, biochem, and quantitative reasoning (math). Then after each packet, you get all of these practice tests for each subject and these are the most helpful! There are so many practice questions so going over them over and over again helped me alot.
Bottom line, I highly recommend the Dr. Collin study guide if you're planning on studying for your PCAT.