I have Pipex's Solo 500 with unlimited bandwidth. It's excellent.
You cant go rong with their service. I imagine u get round 20 to 25kb/s download speed on a decent server.
Nothin else really.
My line was enabled within 10 days of ordering so no complaints. Also it was avalible at 7am on the day on enabling so i managed to have a good go of it before work.