Here is my PF9 with the original parkerized slide done in Wheeler Cerama-coat. One can of the coating cost $22. So far I have done a complete .45 (slide and frame) and now my PF9 slide. I still have some left for another project.
I think it came out pretty good! I also replaced the front sight since you have to cook the slide at 350* for an hour. The front sight would have melted. The marks on the slide are finger prints, not imperfections.