Unc,
I don't want to touch a nerve, but . . . .
Bought a PAYG from Asda a while ago and for every top up you do instore or online you get ( until end of August) 10% extra credit added.
Calls are 16p/minute for first 3 minutes in a day then 8p/minute, to any mobile or landline.
Texts are 10p/text for first 3 in a day then 5p/text.
Paid, I think £15 for a Nokia and £20 for credit, and before we had walked out of the store, I got a text saying that I had £22 of credit.
Even gone one better now:
http://tinyurl.com/57aovtdave