Personally, I don't see this as an issue with GMC at all... it's a Bunnies problem.
I've bought packs of screws from 'em which were returned a week later, unopened, 'cos they were the wrong size. I bought Triton superjaws which were returned later, unopened, 'cos SWMBO got her knickers in a twist. :rolleyes: And so on. It's not an uncommon event.
For all these items they refunded my cash as a matter of store policy (I suspect to quietly get rid of the hairy barefoot loon ASAP, as much as anything ;) ) and I'm damned sure their bloody manufacturers' warranties weren't even a minor consideration. "Give the yeti his money and put the goods back on the shelf."
So why should the brand of this unopened purchase make any difference? :confused: