I've studied from different sources, used Pronotpass (didn't really help), Kaplan 3 day course with book and Q-bank, and even some from AphA book. I'd say overall the Kaplan course and book were very general and simple, Math in the book was the best to review for Naplex. The Q-bank was the best study material for me. Questions were Naplex style, easy to use, covers all the bases for each subject on the exam (except maybe HIV and Cancer) which I didnt see on my real exam anyway. New drugs it doesnt cover either, but ones that have been on the market for more than a year are fair game for the exam.
When I started the Q-bank I scored really low as well, as I went on with the questions and learned more and more from the detailed review after each quiz, I got better at test taking and started getting more right. I recommend it for everyone, its hard but puts the exam into perspective in front of you.
I finished about 80 percent of questions on the Q-bank (contains a little over a thousand). I took the real exam last week, and awaiting my grade. I felt the exam was very difficult and didn't feel too confident at all when I walked out of there. Hopefully I'll have good news to post in a few days. I'll let ya know. =)