Highly rewarding and perfect for refining your techniques as a teacher, if you are looking to move forward in your career then this would be a good place to start.
As an English teacher in Japan a few years back, I was looking for the same thing. An opportunity then came up to be an Assistant Director of Studies in the school I was working for. I applied and was offered the job but felt I needed a little more background knowledge in teaching, and so I dived into the Dip.
There is one thing that doing the Dip taught me the most - that you can not criticise the teaching of others before you have truely criticised your own.
This course made me question every detail of my ability to teach, and this has been vital in my job as an ADoS. One of the most important responsibilities that I have in my work is to regulary watch teacher's lessons and provide feedback.
After doing the Dip I now feel that I can do this with a new confidence.
If you are looking for progress, moving forward in your career and one mighty challenge, sign yourself up to add to your professional growth, maturity and potential future opportunites.