I feel I am well placed to answer this as I have had experience with both Debt Advisory LIne and CCCS. I first went with CCCS in Spetember 2005. With a debt level of 12k and monthly repayments of £450 I was advised by CCCS to contact each of my creditors and offer then £12 a month each, this was all i could afford.
This worked well for a few months, then i discovered that i was still being charged interest and charges and all my debts. To my dispair i discovered my debt level had rose to £15k! It was at this time that a friend of mine went with the Debt Advisory Line. At first I didnt believe that they could freeze the interest and charges, but i though Im getting nowhere with CCCS so i'd give them a go. They restructered my payments down to a total of just £150 a month. I'm hoping to go on an IVA in a few months when my income rises and my advisor has told me that will make me debt free in 5 years!
Im very happy with Debt Advisory Line and i'd advise anybody to give them a try! Good luck!