If you have to achieve a high IELTS score, I would not invest in teachers without IELTS expertise like I did some months ago. From my personal experience I can say that you will need a specific guidance in order to meet the partly weird requirements of the IELTS format. The practice material on the ipassielts website really helped me to develop a good basis for my exam, especially for the listening and writing part, but what really made the difference were the online and skype tutorials with Nigel and Jenny, who exactly know what the examiners are looking for - as a result I was able to improve my writing from 7.0 to 8.0. Not to mention that these tutorials offered unbelievably good value for the money !
My final result was : Listening 9.0, Reading 9.0, Writing 8.0 and Speaking 7.5 with an overall of 8.5!
Natalie - Germany