Had to leave Virgin as I was moving house & they were updating their systems which meant they couldn't connect me for a couple of weeks.
O2 have been first class- texted me at every stage, free wireless modem etc. Everything on time & correct.
Used the tech services (freephone not 0845) and they answered straight away, very polite & helpful. I'm currently running at 18mb/s although only paid for 8! They said this would settle down...
Thoroughly recommended!