I have two-cents here, so I may as well throw them in.
First...congrats on your Sig. I really like Sig pistols, especially the 220.
Second...why the heck would you want to refinish it? Holster wear is like...character marks. My every day carry gun looks so disreputable it has become a joke among my friends. It is a Glock 19 2nd Gen...with a whole LOT of rounds down the pipe. The tenifer finish is shiny from a gazbillion presentations from the holster. The night sights recently had to be replaced with a new set of Trijicons after they went dim. New Wolff springs every 20,000 rounds whether they need replacing or not. Ghost Rocket 3.5 connector....the outside looks like my first car....but inside...she is still sweeter than my wife when I first met her.