For £2o I won't be bothering with a warranty claim, I can waste more than that on coffee in a week!
However I don't see how using a card in a dash cam voids the warranty, I do less then 7k miles a year so the card gets very little use, so I guess I would argue the case if I could be bothered, which for £20 I don't think I'll be bothering. As I say My card has been in the camera for 10 months and still working fine if it lasts another 10 months then great if not I'll just stick another card in.
However I don't see how using a card in a dash cam voids the warranty, I do less then 7k miles a year so the card gets very little use, so I guess I would argue the case if I could be bothered, which for £20 I don't think I'll be bothering. As I say My card has been in the camera for 10 months and still working fine if it lasts another 10 months then great if not I'll just stick another card in.