I've got a spare set of wheels sitting in the outhouse and i'm wondering about fitting them out with a set of winter tyres.

Seeing as we get snow and ice so infrequently(but when we do it's carnage) is it worthwhile getting a set of winter tyres, putting them on in say November and taking them off in March and then swapping back to 'summer ones'

Most of the weather will be wet, so what's the wear rate/grip like for winter tyres, as compared to 'summer' ones?