This deal seems to be making waves Bob - VM are on the back foot now - I give it a month before they let anyone use their unlimited sim rather than just customers.
I get 200GB + rollover for £20 a month -I sent an e-mail asking why they gave me 300GB last month instead of 225 which was 25GB rollover data. I've had an e-mail back today to say my data rollover will be 100GB from now on due to "competition available to me"
I will never use 300GB in a month unless I hammer in on purpose - but at 71/45 I can't really fault it.
I did try the Three £22 deal - but the speed was slow for me even after a capacity upgrade at the cell.. so this is about the best I will get in this area.