I took forever to do MD the first time around. That book discouraged me so much, but I don't regret putting all that time into it. I went through the 2nd time only to test 3 or 4 (got lazy haha), and then I just reviewed the p-value questions in the later tests. I also went through some of datqvault QR, which I thought was great bc you got to see more of a variety of questions. Difficulty level is between datqvault and MD. Just know your trig identities, geometry formulas (circles, cylinders, etc) and how to make good educated guesses. I had 6-7 problems I marked, and I went back and just manipulated the answer choices to reach a "solid" guess. This can probably bring your score up a few pts. Made a 30 somehow miraculously, but the above tips definitely helped me.