I went the route of turning an old mountain bike into my dedicated winter bike. It was an easier choice for me, as my other bikes have 27" wheels, so they won't accommodate studded tires anyway.

If you ride both bikes during the winter, then you have to winterize both of them, because the salt will always be on the streets. I decided to just ride the winter bike throughout the season, to keep the salt and muck off the other bikes. The studs slowed me down, but not as much as I imagined they would.

If you don't already have fenders, they are particularly beneficial during the winter.

People have various rituals for prepping and cleaning winter bikes. I coated all of the exposed steel parts of my bike with chainsaw bar oil, which is particularly sticky, and re-applied it a few times through the season. It was a horrid mess, but the only parts that rusted were the ones that I missed. I didn't hose the bike down until spring.