i do hope I am not testing fate! I have been with Vodaphone (dreadful customer care) and Orange (service became worse and worse as prices went up and up), having had a mobile for 20 years. I actually have 6 numbers on my contract. O2 have astounded me with their service and although I sympathise with those who have had bad experiences, be very careful who you move too. I'm sure if you speak to O2 complaints department (free of charge on your handset) they will be happy to help as they do seem to be concerned with customers and their problems.