I'm smack dab in the middle of a Testmasters course right now. Admittedly, I've been a slacker and haven't been doing the homework. However, the material is still making sense to me, and I plan to use my free time after the class is done to master the concepts I'm learning now. The online material they provide is very helpful as well. There are explanations to many, many of the questions, access to a helpline, and even video explanations for some of the questions. My teacher is really good too, which I hear can make all the difference. So, look into who the teacher is going to be and try to meet them ahead of time if possible to get an idea of what to expect.