Honestly I'd recommend Smarty for people using 0-12GB and giffgaff for people using 12GB+ because Smarty have a much simpler website and set-up, so until they become more expensive, they are the better choice, (assuming similar network service), for the majority of people who just want a simple, clear service.
They also have a much better referral program where if you refer someone, no matter what package you're on, you get month is entirely free of charge. And I know you can do that with giffgaff but with Smarty there's no faffing around waiting six months and no faffing around with PayPal.
Support via email, live chat and the usual social media channels so there's no dodgy, (slow, buggy), website to deal with just seals the deal really because most people would find it easier to use email or social media as opposed to a forum like this, especially given all the problems which we have seen this place have always but especially lately.
I'm sorry if you think I'm singling you out, but so often I hear things like I've quoted and they're posted with no explanation at all, except "payback" is mentioned, which makes it seem as though your position is that you think giffgaff is better because they bribe you.
It would be much better for the company if you gave an honest appraisal of their services detailing why you think giffgaff are better than *insert network here* rather than just basically saying, "Well giffgaff bribe me so they're the best!", because such comments are one of the biggest reasons that I have found for people to be scornful of a suggestion that they consider giving giffgaff a go, and it's a significant disadvantage to giffgaff because they're the only network I ever hear being discarded for that reason.