This is absolutely brilliant. Whilst I'm not an absolute beginner at studying Japanese, this is the first time that I've had confidence to actually SPEAK the language. The course is a constant challenge to SPEAK. It has probably been useful that I already have a good Japanese vocabulary, and that I can understand a lot of Japanese, however, no other materials I have ever used have prompted me to SPEAK Japanese.
I speak reasonable Japanese, and got this as a curiosity. Comparing my level of improvement since I started years ago and the students on this audio book, I think if I ever learn another language I'll always start with the Michel Thomas Method.