Mr CRX and i both had 3 mobiles. we cancelled them as soon as our contract ended.
problems we had were:
they kept turning on the voicemail on his mobile, when he specifically asked it to be off as he has an alarm call go to his mobile that he has to pick up.
we went to france, called before we wetnand 3 assured us that his was set for roaming and mine wasnt but that they had changed mine over. When we got there ghis wasnt activated and it took 3 days and 5 calls to get it activated. They refused to refund the costs of the calls he made to them
The signal would drop out as soon as we answered calls, meaning that we had to call people back, perhaps the cynic in me thinks that it was all to line the pockets of 3 as the signal came back so we could return the call.
When we tried to give30 days notice 30 days befopre the end of contract they refused to accept it until the end of contract.
when we did cancel it they sent two bills for same period and it took 6 weeks to get one credited (on each phone)
They also phoned almost every day for that 6 weeks on our new provider as we has ported the numbers over.
Oh and im not sure where their call centres / customer services are but it was very difficult to speak to people who could understand English very well and didnt just speak from a prompt card. Even phones 4 u, who we got the cpntract from, refused to speak to them onour behalf as they said they have same problems getting through to them.