I felt that TDC narrowed the scope of material down to the most important material. I think I failed the first time, because the other agency I used incorporated too much information. My brain was on overload. With TDC, I felt that there was a nice balance of information, and the audios make it great for me to review material during lunch, while driving, or from anywhere I had a moment. Also, I enjoyed all of the practice exams, because I felt very prepared during the actual exam.