3 are an awful company-I had trial with them for two weeks. They:
-tried to mislead me by barefaced lying into making calls and texts on the trial SIM which would have tied me in for two years
-when I couldn't get a signal, told me that 'the engineers have just discovered that the antennae are facing into the park rather than the town and are going to be turning them around any day now'
- got really aggressive and personally rude when I tried to cancel the trial

Also their signal was almost non-existent

Apart from that they were OK