I look out a CDL a couple of years ago.
I chose Barclays, because their APR was the lowest and the repayment terms suited me. It did take about 4 weeks to process, though that may have been unusually long, because my course was a bit complicated and they kept on writing to me for proof of this and that.
I took out a loan of £4000, I think the maximum is £8000. I've just started the repayments on it, £135 per month for 36 months. It's possible to defer the repayments when you've finished studying if you haven't found work, or there is a change in circumstances.
Hope that's helpful, I'll post again if anything else comes to mind, they are a great idea, I couldn't have funded my course without it.