I used Kaplan blue book's 6-chapter QR section, I didn't find it usefull at all. DAT desteroyer has like 150 QR problems, but I didn't like them at all either. I think MATH Desteroyer (for me personally) is the best option out there.... Of course I am only saying this cause I have no experience with Crack DAT MATH.
But lets be realistic here, those 440 problems on the MATH destroyer, man if someone was religious enough to master them, I can't imagine seeing that person land anything lower than a 20...