Worst thing I have ever done is going with Three. As some more reviews have experience below, they go the extra length to get as much money off you as possible, even if it means setting up another account in your name with another direct debit that will charge you the same bill twice a month ongoing until you realise! That is what happened to me and when I realised and complaint, it took many months for them to admit it was their wrong doing. After getting a refund, I was then sent to debt collection for the money they had just refunded me. And I have had the debt collection agency calling, sending emails, letters pretty much every day for months now! Whenever you try to get on the phone and try to end this madness, nobody listens, they just say they will look into it and phone back and that never happens. Two years of stress I have had with this, affecting my credit score, giving me unthinkable grief. Avoid at all costs.