i'm with O2 and have never had any problems with them apart from being inundated with messages from them telling me about all the deals they offer. I would love to take them up on some of them but I always seem to get their texts when i'm driving, really busy, have company or am asleep!! Then having a bit of a 'dicky' memory I always forget to do something about it when I get a min.
I just top it up when it runs out! When I am topping it up it tells me that i am on 'anybody' or 'everybody' cant remember
Bonny x