I tend to use whatever I've got on hand because I'm trying to reduce the amount of lubes and fluids in my house by using them up. I'm also trying to stop using sprays, because the overspray tends to get on my garage floor. Probably the most protective stuff I've used is chainsaw oil, which is really thick and sticky, applied with a little brush. I've considered varnish or linseed oil. I don't go on long recreational rides during the winter, so my speedy bikes are put away, and my winter bike doesn't need to be clean or pretty.
I figure, if it's oily, then it will repel water and whatever salt is dissolved in water. If it's sticky, then it will stay put for a while. That's about how much thought I put into it.