What you are doing right and the others aren't is two fold.

First of all, you have a progressive series. A person can actually start from the beginning and work their way up to a conversational level. All the words are accounted for. You remind people of what is new and what has been covered already. You remind them in Chinese and use English sparingly.

This is the way that it should be done. After the initial stages, a language should be taught in the target language as much as possible.

The second thing – Lessons are introduced in Chinese.

I've been with you for about 2 months and I think your course is the best available !

I'm interested in Chinese culture. I spend about an hour and a half each day commuting by car, and I was looking for something to do with that time rather than waste it. I hit upon learning Mandarin via podcasts. I think I found your site by a random Google search. I tried "chinesepod"... they are good too, but because your approach is much more progressive I'm learning a lot more from you, and it's sticking !