Bimbler, I’ve just done the same calculation.
My current HTC desire (2.5 years old) is costing me £21/month – £504 over 2 years (300 mins, far too many texts, 500Mb data)
A SIM only deal from Tesco (250 mins, gazillions of texts, 1Gb data) = £10/month – £240 over 2 years
Nexus 4 handset – 8Gb version = £239.
Therefore – get the lot from Vodafone = £504* over 2 years vs DIY of £480 over 2 years (inc stumping £239 up front).
Can I be arsed? hmmmm…. it sounded good when I first thought about it, now I’m not so sure.
* of course, this figure is only valid if I can get Vodafone to “upgrade” my phone to something decent for free. When I tried a few months ago, they weren’t interested as my tariff is pretty good.