I don't think polished blades rust less than satin. If they're kept oiled neither will rust. If not, both will rust.
However, if you like the polished look it's not hard to polish a satin finish. Start with progressively finer grades of sandpaper and then work up to polishing powders. There's "red rouge" and a white version that will leave your blade highly polished. Watch out for the edges and point of the blade. Fingers don't grow back and deep cuts take a long time to heal.
The main trick is don't start with the higher grits of sandpaper (600 grit and up). If you start too high it won't take out the deeper scratches that are part of a satin finish. You'll end up with a highly polished finish that makes the deeper scratches stand out more than if you left the blade at satin. I learned that the hard way.
-- Dave