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.

I am really enjoying the course and find it very helpful.

It's a great idea. Here in the UK, it's difficult to hear Mandarin Chinese spoken if you don't know Chinese people personally. I am currently enrolled on a Mandarin Chinese course but find it is very book-centred. Writing and reading (pinyin and characters) is not too hard for 'visual' learners like myself but if you need practice in hearing the language, Chinese Learn Online is just ideal. Thank you very much for your efforts.