[Nugget]

Purely from a phone point of view, the network's academic - realistically, you don't need any accessories as, as has already been said, it comes with headphones which are good enough and, as long as you get a decent M2 card, you'll get loads on it.

For what it's worth, I'm on O2 (although it's the black phone I've got), and a friend's on T-Mobile, and there isn't much to choose btetween the two. Mind you, Mrs Nug's just got a different model on 3, and their contracts appear to be much better than O2...