Hey! First off, good luck, and just remember how hard you have worked, and stay confident in your approach. Do not spend a lot of time second guessing yourself, as it will generally just hurt. DAT BC is legit. So legit, that it in fact cannot quit. The PAT section is so good, I got like for my last 5 tests on PAT BC 18/19/19/20/20 and got a 24 on the real thing. Spend time using all the generators that Ari has put up, they are incredibly helpful, and are great review for a day or two before you take the exam.
The Math section is way harder. The final QR section I took on BC it said "Score Less than 16," and I got a 19 on the real DAT. I also suck at math generally, though.
The sciences are great and I would spend time going under each concept set of questions and making sure you understand why the answers are what they are, and why the others are not correct. Make sure you also watch any video solutions for Orgo if you have trouble, I did not see them until the day before my exam and spent a lot of time going over them (scored a 23 on OC). The GC section is great too, and I was even surprised by my score because I felt most comfortable on GC going into he exam, but I just got a harder version I think. RC is also great on BC as well, it was a little harder than the real one, but I have always been good at RC too, so maybe it was just me.
Overall, DAT BC should be a staple in your study arsenal because it is that comparable to the real thing (only it's a little harder) and its a great overall resource to have. Good Luck on your exam, and don't worry, you'll CRUSH it!