If you go the Cambridge website and put in your postcode the CDC in your area will come up. Read their "blurb" and contact them directly from there. You will get a good idea from their write up whether they are the sort of person you would like to work with. I think chosing a CDC is quiet personal and what somebody else thinks is good might be completely different to your own expectations. I got a good idea of what I wanted from the website Hope this is helpful!