I used Kaplan, which was good for bio and chem I thought. I also used Barron's, some random question book that I can't find the name of online, and all the practice tests through Pearson. Getting all of that wasn't too much. I have no experience with the Dr. Collins review.
Take practice tests, find out what you are weakest at, and practice the crap out of that. Then take more tests to get used to the speed and timing. Math and chemistry can get time crunched during the test. They may not be questions that you can't figure out, but you need to get through them quickly and that takes practice. I got multiple books to be sure I wouldn't be blindsided by questions being asked in a different manner between study guides.
Got a 99 first shot. I studied probably 2-3 hours a day, more on weekends, for about 6 weeks. Good luck!