I've had a sim for about 2 wks & have recently added another in a dongle. Today I've had my number ported from AsdaMobile: except it hasn't, as yet!
I put 1/2 a gig on the dongle sim to check it out. Speed ok, but that's down to O2. But I seem to have used 450 meg in 2/3 days. You must be joking! Bullshit!
To round up: giffgaff seems to be an amateur affair, which doesn't suit me. I, in common with most phone users want a proffesional well-run service; & we're prepared to pay for it. The price difference between this & O2 or T-Mobile, for instance, is not sufficient to make it worth anyone's while to accept such a poorly organised venture.
I think I'll cut my losses & return to the real world. With all the big boys faults, at least they offer a properly organised facility, & at about only 20/30% more than giffgaff.