I decided to upgrade from version 1 of this product because I wanted the auto-grading, but that wasn't the only improvement. This version has more content and, while it does review the previous year's work, it doesn't take a tedious amount to accomplish it. This makes the pace of the book better. I've tried several popular math curricula with my students, but TT text is the one we keep returning to. Overall, TT is an absolutely fantastic product for both the mathphobic and those who like math.
My son loves Teaching Textbooks Pre-Algebra. The lessons are clearly explained and easy to understand. Each lesson has interactive practice with new concepts before the problem section begins. Also the "study buddy" feature is fun and encouraging. Overall this was an excellant fit for our 7th grade homeschool math program.