Ok this is a redemption offer, but if you can afford £35 a month to come out of your account you get a cheque automatically raised for £136 after two months and then you need to send a few bills off to claim the further refund.
e2save is the Carphone Warehouse, their cheque back process is good, I have used it before, they text you from recieving your bill to texting when payment is processed.
Free phone too & a free pair of portable speakers!!!
Not for me as I have a company phone, but a present for Mum for pence per month!