I suppose if I start a thread about beer, there's always gonna be macho-types hanging around telling me to drink cans faster than I can open them, but anyway....
If there is something that can prevent my hands from freezing whilst I have a few beers at a party and simultaneously keeping the can cooler for longer, then I'll happily use it.
Yeah, a lot of them do have shitty designs too, but find one with a good design and you're set!