Practice, Practice, Practice!
The goal is to increase reading speed and comprehension levels and this can be easily accomplished by old fashion reading. If you dedicate just 30 minutes a day to reading while preparing for the DAT that's a lot of reading accomplished over the course of your preparation. Make it a habit to read just before bed, not on a computer or phone but an actual book or magazine, it will also help fall asleep. Old school still works for certain things. From experience trying to predict a score for reading using a timed test is not possible there are too many variables . We offer free daily reading passages in our study group that can help with practice, others can chime in about the other products you mentioned.
Just my 2 cents
Nancy, co/owner, Orgoman, DAT Destroyer