I have done several courses with I-to-I, Teaching Business English, Teaching English Online and 120hr TEFL/TESOL. I have found all of them very beneficial and extremely helpful. The staff are extremely supportive and the Tutor feed back is excellent. If you plan to teach Online, I recommend you do the Online course, as this opened my eyes as to what is out there with regard to the internet, i.e. blogs, hangouts etc.. The Course is full of useful resources and gives you, as a potential teacher, a great insight. The same applies for the Business English Course, they have helped me immensely, I am very pleased I completed them.