I can only comment on the DAT Destroyer by saying our classroom students who complete all the work in the Math Destroyer, including the new QC problems we have added generally score 18 or better. It takes work to score high in any section of the DAT because there are so many versions, you might have trig and geometry, maybe not, you might have a lot of prob and stats, maybe not, a lot of word problems. maybe not. See my point? There is no way predict what you will be presented. Also you need a good strategy when taking the QR, one of the best is don't spend a lot of time on a problem, if you can't solve it quickly move on, there will be easier problems ahead.
Hope this helps..
BTW, if you are pushed for time go through the math destroyer look for the type of problems you struggle with and do those. NO need to waste time on problems you can easily solve .
Good luck on your DAT!