Any of the modern firearms coatings, if properly applied will provides years of durable good looking service for you.
Remember Thermal or baked on finishes will require that what ever you coat being able to fit in an oven. From personal expierence, I would also recommend that you plan on doing this (baking) when no one else is home. Some people get a little upset when you bake parts in their oven.
For ease of use and application its tough to beat DuraCoat. It dosent require baking and is a very durable finish when fully cured. It is a two part coating which will require mixing the hardener into the coating but its not very tough to do. Remember 1 teaspoon of hardener to 4 tablespons of coating.
KG or Norrell's are also a great coating's which is cured when you take it out of the oven. I would recommend preheating of parts but some guys dont preheat and their stuff turns out good.
Most manufacturer's recommend blasting with a dry mesh media prior to applying a coating. Do not use glass or plastic beads they will ineffect polish the surface making it tougher for the coating to adhere properly.
If you have any question give me a call. I'm usually in the shop until about 10pm CST.
Joe