I'm really happy with EDF so far after terrible experiences with E.on. Customer service has been good, although they lose a star for long wait times.
Currently on prepayment meter but they are changing them to direct debit meters in the next couple of weeks free of charge!! Not used the online system to give meter readings etc. but will update review when I do.
Additional 24/09/12: EDF now deserve 5 starts - their customer service has renewed my faith that customer service still exists in some companies. They respond to emails, they call back when they say they will, and will go out of their way to keep you a happy customer! To avoid long wait times just drop them an email and they will call you back, or email you the information you need.
Really really impressed! Oh, their prices are really good too!
To reply as a company, please log in to your business account.