I think its important to bear in mind that Kaplan is a business which in regard to DAT prep has little competition. Additionally DAT prep is an extremely small part of the business when compared with SAT, GRE, GMAT, LSAT and MCAT. As a result, there is no great incentive to optimize the material, because where else are you going to go. It appeared to me that much of the study material was recycled from one of the other exams. This obviously does not apply to the PAT for which their study material was close to useless, though their techniques were very good. It seemed that much of the QR came directly from GRE and GMAT, while the sciences came from GRE and MCAT. This is backed up by the fact that the online tutorials often discussed taking the MCAT rather than the DAT. Now that said I felt the Kaplan material was sufficient for preparation but there will be some questions(such as work problems in QR) that will probably not be seen on the real DAT. Good Luck!