<p>I took/am taking both courses. Ivy insider was helpful as the teachers know more than PR teachers, but they are still reading from the book. PR tests are more helpful though. There are only 4 Ivy Insiders tests, but the 11 tests book from PR and the 4 diagnostic tests help. I think as a combo, they help. The annoying thing is they teach in slightly different strategies, so sometimes in their tests you have to know what answer they WANT you to pick. I think I stick with CB prep tests after i finish the courses and just do a lot of practice. Both courses together improved my score about 200-300 points. Oddly, i normally get either the Critical reading or writing section of a test almost perfectly but bomb the other one. In the end, my score averages out :(</p>