I am considering the purchase of a quality set of studded tires for occasional use during icy periods (a couple of weeks per year tops). They will not be used often, but they will allow me to continue my daily rides and run my errands even during those annoying icy patches.

I can put the tires on my 26" mountain bike, which will require the addition of fenders, or on my 20" dahon which already has fenders and is my goto bike for errands. My question for those of you who have used such tires on both types of bikes, is there one or the other that has superior performance/safety on the ice or is it a wash?