I have a close Chinese friend who listened to some of the recordings on my IPod - she said go with CLO. She constantly remarks on my great accent which she says is always the biggest problem.
I travel a great deal and knowing Chinese, even a little, can only be helpful when 1/4 to 1/3 of the worlds' population speaks Mandarin Chinese. You are doing a great job - I seem to be going very slowly; however, my friend says I am not but rather she is impressed with where I am and again is most concerned about the correct accent.

My wife and I have used several online Mandarin teaching sites. For us, Chinese Learn Online is the most comprehensive, user friendly and effective. The content, pacing, review, and reinforcement are superior, and we feel like we're in a class with an instructor who really cares about our success. We have enjoyed the podcasts and lessons so much that we'll continue when we return from China. That's about the best feedback you can get.