I've taken TPR classroom course recently. The way the classroom course works is they give you a giant stack of review books to work through at home while the instructor spends the majority of class time going over material and two or three in-class passages. I think TPR gives students way more review material than EK or Kaplan. In addition, TPR breaks classes down by subject and the instructor is different for each while I believe Kaplan has one instructor for the course.
I think the quality of the class depends on your instructors. Some are more helpful/knowledgeable than others. When I took the course I had complete confidence in my ochem and gchem instructors and went to every class while I stopped going to bio because the instructor kept confusing herself during lectures. Personally, I don't really think you need the instructor to teach you the material, especially since it should be a review. Rather, the course is a convenient way to get study materials and practice exams, help keep you focused and on-track, find study buddies, and get your questions answered about material or practice problems. The instructors usually try to give you tips about the topics to focus on, which question types are commonly seen, and how to work through the problems.
Overall, the course is most helpful if it's been a while since you completed undergrad or if you're a non-science major. Good luck studying!
