Engadget has a rather labyrinthian post on carrier/data options in the UK.
We're going to try to break it down, but feel free to wade through the long post at Engadget. Our eyes started to cross, to whit:
Orange and O2 were the first to drop with handset pricing and full contract details, with Vodafone following. T-Mobile, Three, and Tesco Mobile will follow in the coming days.
O2 says 97 percent of all users aren't going to go over 500MB of month, and most of O2's deals are capped at that number, with only the top two stretching to 750MB. Whereas Orange has a 750MB "fair usage policy" across the board.
There's an awful lot of price overlap on the two-year deals offered by O2 and Orange; this is evidenced both by nearly identical total cost of ownership on price plans between ¬£35 and ¬£45 and similar talk time.
The price differences are a bit more pronounced on shorter-term agreements. O2 beats of Orange when it comes to total cost, and offers the cheapest possible iPhone 4 plus service deal, with an 18-month contracts costing ¬£30 per.
There is a disparity in 3G data allowance from the two networks, while noting that Orange will also let you buy an add-on 3GB tethering bundle for ¬£5 extra — something that O2 is unwilling to match.
O2 also prices its iPhone 4s cheaper on its lowest 18-month tariffs than it does on its cheapest 24-month ones. That might be a mistake soon to be corrected, but it makes for an interesting subsidy and helps deliver the cheapest 16GB iPhone 4.
On the basis of the networks who've announced pricing so far, we recommend O2, and trying to control our bandwidth usage.
Orange just isn't doing enough to encourage defection from the longtime exclusive iPhone carrier in the UK.
Vodafone is the only iPhone carrier to give its users a full 1GB of 3G data. Like Orange it offers tethering options, but its prices are far not cheap. The same ¬£5 tethering bundle that gets you 3GB with Orange will only get you 500MB with Vodafone.
What we gather is that actual pricing differences between the networks will be narrow. It obviously depends on what you need. What's could make the difference for you in the end is whether or not you need to tether your laptop to your iPhone, whether you can fit in under O2's 500MB data cap, and whether 75 minutes of free talk time is something you can live with.
Of course, the article does not even begin to talk about the opportunities presented by buying the handset outright and hunting around for the best SIM-only deal.
Was that any help at all? Our head is spinning.
The bottom line? We'd probably go with O2, but YMMV.