Well, the best teflon moly coaters always park the firearm first. The park gives the teflon, be it Tuff Coat, Lauers what ever. It has been pr oven that applying these coatings over bear metal really do not last. Park is a porous coating. That is why it sucks oil up. When used in conjunction with moly telfon coatings it does the same thing, it pulls into the park giving a much more resilient finish. Definitely less chance of the teflon flaking off.
If someone is telling you that this is a special process, they are BS'ing you. Every coating company sells a park based primer and recommends its usage. I never do a teflon moly finish without parking it first.
The two companies I would recommend are Mac's Shootin' Iron Restorations, Arizona Response System and Birdsong T.
Be aware you can ship your firearm to these guys, the cost for none FFL's has rocketed through the roof. If you go to the local gunshop and ask, I will bet there is someone in your area that does this work. Believe it or not, it is not that hard.
Just so you understand:
1) strip the firearm
2) degrease squeaky clean
3) Bead blast with 70-80 grit aluminum oxide
4) degrease again
5) put in park bath
7) warm gun to about 100 degrees
8) spray on teflon/moly
9) bake in oven for couple hours
10) when cooled down, put gun back together.
Oh yeah, I forgot to add, park will not take on stainless or aluminum. Stainless is dicely with teflon moly, not matter what anyone says. And aluminum will take the tflon moly ok, but there are some ceramic based spray on finishes that work much better.