No, as in the damage to radiators that need replacement seems to be the internals cracking from the inside vs external debris damaging the fins and damaging the radiator from the outside.
Must admit I've not heard of radiators failing from internal cracking, surely that would be a design flaw? I would imagine it would also be fairly well publicised! I've had a couple fail over the years and each one has been stone damage.
Back to the Evotech guards - no difference in temperature, very happy with them. I'm sure the Cox guards are good but if I'm paying that amount of money for a guard then I don't expect to have to take a Dremmel to it!