Phoned up carphone warehouse to cancel and they have given this deal.
Network: O2 (CPW)
Line rental - 35.00 less 2.5% vat = £34.12
Cah Back = £540 ( 3instalments x £180.00)
Contract = 18 months
Final value after cash back = ((34.12 * 18) - 540 ) / 18 = £4.12 per month
This is a good deal as it has got unlimited internet as they are selling £7.50 per month for mobile internet alone.