Samsung S5 on O2 refresh back in stock, its refurbished but priced at £269.
Choose any of the £269.00 tariff pay up front, as soon as receive the phone cancel the air time, can also request unlock code but may need to wait for the phone number to register on the system.
Cheap way to get the S5, cheaper than the vodafone deal (thats ringing hot! at the min). Not sure how many in stock so be quick!