I just returned a pair of jogging pants that had come apart slightly on the seam. I didn't have the receipt anymore but I returned them anyway but was quite prepared to be told nothing could be done.
The girl at customer service said it was a discontinued line and couldn't get a price up so asked me what I'd paid for them. I wasn't sure but I said I thought they were £8. She said fine, did I want to go and choose something else to that value.
I was so pleased. Top marks to Primark for their customer service.