Giffgaff is a different network to the big ones, it has generous tariffs, competitions with big prizes, Payback and a friendly community. I think it has something for everyone with their low standard rates and generous Goodybags with unlimited internet with no FUP. There's no customer service line which keeps costs low and they have the community to help with problems; the community it made up of other giffgaff members who want to help and get paid for doing so (through Payback). If they can't solve your problem, they have several giffgaff staff, called 'Educators' on the forum who are usually online and ready to help. The only hassle you'll have joining giffgaff is unlocking your phone and transferring your number. There seem to be lots of problems when it comes to transferring numbers, but I didn't transfer mine from Orange so I haven't had any problems with giffgaff before. Overall, giffgaff's a great network for anyone who's stuck on pricey PAYG rates and uses O2's signal, so has pretty good coverage.