Cost of a 24 month comparable contract between 3 and giffgaff. 24 months is 3's minimum term. iPhone 4 16Gb model...
3 - £30 = 500 mins, 5000 texts, 500mb internet
GG - £10 = 250 mins, ultd texts, ultd internet
I know 3 offer double the minutes, but have capped texts and internet, and it's their cheapest contract that come close to comparing with GG.
3 - Phone cost = £99
GG - Phone cost = £499 (or is it £512 now with VAT increase?)
3 - £99 + (£30 x 24) = £819
GG - £499 + (£10 x £24) = £739
And if you go with 3, from a technical point of view you are on the poorer performing network. O2 (and Vodafone when they pull their finger out) are allowed to use the UMTS900 band, which requires minor modifications to their existing equipment. Three don't have any 900MHz equipment so are stuck with their 2100MHz equipment which can't really penetrate well in cities. I've got first hand experience with this UMTS900 band on Giffgaff/O2 and it makes all the difference... depending on your location. Which is ultimately what it all boils down to. Who provide the best service where you live.
Although stating Three over and over again are the cheapest is incorrect.