Originally Posted by
Kevincm
As there is a group of you, you might want to all stay on the same network and set the tariff up so you can take advantage of network-to-network calls (eg T-mobile network to network calls are 15p/m on one plan, yet on an everyone plan, that same call is 25p/m).
In reality, you can't go too far wrong. Alternatively ask a UK flyertalker... some of us get 4 SIM cards for filling out a form via QuidCo which can be sent onwards....
Doing a bit of digging from the sites listed above, I discovered that O2 has a top-off plan that, at the 15 pound level, gives unlimited calls/text to other O2 phones.
Economically speaking, there's a definitive breakpoint where if we're under it, then a 10 pound topoff was all we need, but if we're over, then we were much better off with the O2 plan in the first place. I'm not sure if these will be used all that much - depends how much the group wants to separate or stick together.
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The 'ask for a free sim card' from a fellow flyertalker thing intrigues me. I'm not really much more than a lurker here, so have very little to offer, but if someone were able to offer 3 same-network SIM cards, they would have my gratitude.