I just love this course and tell everybody about it at the Chinese school where I have a 2 1/2 hour-lesson once a week. It complements and puts me several steps ahead of my presential classes - everybody feels awed by the sentences I'm able to build, my vocabulary and sometimes the explanations about a certain term that even the Chinese teacher is not able to explain (sometimes it's difficult for a native person to explain the mechanism of his own language, because it's just so intuitive and automatic for him).

I think your course is well organised and is great for beginners as well as more advanced. I've only listened to about 30 lessons so far. I like that at any time I can review lessons. It's also great to be listening to native speakers. Unfortunately there is no short cut to learning a new language especially when it comes to tonal Asian languages. Conversation context is great.

Seeing the pinyin makes a big difference. I like to picture it in my head when composing sentences and having the tones works helps a lot. Your product is great! Especially now I can visualise the tones.