Sure man, I'd love to help.
I think the most effective tool when it comes to Biology/QR practice is the DAT Destroyer. I really felt like I scored 20+ in RQ but was shocked to see I only scored 18. Keep doing those math destroyer tests and I'm pretty sure you can score 20+. I did 3 of them and still found most of the questions I practiced in the actual test. My other study tool for Biology was the Kaplan book.
For OGC, I used Chad's videos and some of my second year notes. I felt like the exam was very very basic. no big molecules and very simple questions. Nothing complex. For GC, I'm obviously not in position to give advice, but I thought alot of the questions in the exam were pretty similar to DAT Destroyer, I just wasn't lucky to come up with the final answer.
For PAT, Crack the DAT HELPS ALOTTT! I have done alot of practice and thought I was set, but the angle ranking was extremely difficult. Keyholes, Cubes, Folding and Hole punches are very similar to Crack the DAT.
I also did 10 practice tests for reading with Crack the dat. Questions were not similar but overall difficulty was similar.
Let me know if you have any more questions.