Good stuff, cheers guys. The premise of what they do is to me genius. I dont want to pay for overheads for stuff I will never use, which is exactly what they remove by having support via forum/email. Technically they are O2 at heart and O2 do all the provisioning for them, so from a hardware/network view, they should be rock solid.
I am coming to the end of my O2 contract and can swap from spending ~£40pm to £10pm on GG.
Looks like I'll be ordering a GG sim soon!