I was thinking of getting their 50mbit Broadband offer but noone can confirm if I can cancel my contract if they start their throttling nonsense so I'll stick to my 2months free/£100 cashback resulting in a profit O2 Broadband (still need to pay that BT landline though, but comes to a third of what I'd pay VM)
50mbit on their current offer on this £150 cashback:
Line: £285 total paid or £23.75/m average
No Line: £291 total paid or £24.25/m average
£6 not to have a line...