No direct experience, but several comments come to mind...
► Most stainless is not "stainless". As a material it is a category of steels containing multiple groups of alloys. Some will rust, others will stay rust-free as long as they are not touching other rusty steel parts. So "stainless" is not always as wonderful as first imagined. **
► Most of your better stainless parts that actually do resist rust go though a secondary process called passivation. That's simply an acid dip that removes all the iron molecules from the surface, leaving only chrome and nickel. You might ask if these parts are passivated.
► Since the (much larger) steel backing on the friction pad is probably already rusting, it's not clear what advantage the smaller "rust-free" pins might offer.

If you want to spend money on your front brakes, IMHO you'll get a lot more bang for your buck by 1) replacing the fluid, and 2) replacing the rubber lines with what's generally called "stainless steel brake hoses".

Hope this helps!

** As an experiment, lay a uncoated steel part (like a common nail) in your stainless steel kitchen sink for a week. But first, hide all the kitchen knives from your spouse. 😛