I cant speak for CATS but I can recommend Bristol.
The school is first class as are their books and the cd they produce.
I wouldnt let the locality of a school put you off, as during the 2 weeks brush ups its very important to be 100% focused, and staying somewhere away from the daily destractions of home life is very important.
The atmosphere at Bristol is very relaxed and the staff are very willing to assist you in every way.
For customer service I cant fault Bristol, in fact I cant fault them in any way.
good luck wherever you go.