i have a dedicated winter commuter: IGH disc brake hybrid with full fenders and it wears schwalbe marathon winter studs 365 days/year so it's
always ready to go, even if we get a freak ice storm in july
i have a dedicated regular commuter: disc brake CX bike with full fenders and 700x28 conti GP 4 seasons; it sees the
VAST bulk of my commuting mileage.
i also have a light and fast Ti road bike that i also sometimes commute on when the weather is ideal (it doesn't have fenders, so i try not to ride it in the rain).
i really, really like having a dedicated winter bike because it allows me to just leave the studs on it all the time without futzing around with tire or wheelset swaps. it was an ideal situation this past winter when our weather was so freaking up and down that i was switching back and forth between my winter bike and my regular commuter seemingly every couple of days. i didn't have to plan anything out, if i woke up and we got frozen precipitation overnight, i'd just hop on the winter bike and go. if it was above freezing or i knew the streets were still bone dry, i'd just hop on my regular bike and go. i like things that are easy like that. in the old days when i only had one commuter bike and did the tire swap thing, i found that arrangement to be far less than ideal, hence the dedicated winter bike purchase several years ago.