Cheapest I've seen for a digital copy. £36.99 on the PS store...
Or get for £35.14 by getting a £40 PSN topup from cdkeys using the FB 5% code and have £3 credit left over.
Spend £31.25 IF like me you have a couple of quid left in your PSN wallet then get the £35 voucher for £31.25 using the FB 5% code.
Technically this costs £33.24 as you are using a left over £1.99
Or you can pay the odd £1.99 by credit card apparently, Thanks to Jackdugher