Hi,
So I emailed Chad about the same thing. Essentially, chemistryprep is not specifically designed for the DAT - it will cover all the material on the DAT and then more. It is about 20 hours of gen chemistry, compared to about 13 hours on coursesaver. I plan on using ChemistryPrep simply because its way cheaper....you can get 6 months of subscription for 40$, meanwhile 1 month of coursesaver is 50$. Just compare the cDAT (if youre canadian) requirements for general chemistry, with his videos - and adjust accordingly.
You can also use chadsvideos.com, which have similar videos to chemistryprep, but its different in a few ways:
1) It doesnt have built in quizzes/practice
2) They're of a lower quality
3) They're not broken down into individual sections
4) The outline isn't as nice