Jeffery,
I've an FN49 military rifle that was cleaned, prepped and refinished more than 35 years ago with original Gun Kote (before Brownell's acquired the product line). It still looks like the original parkerized finish, with no chips, flaking or scratches. Minor scuff marks are hardly visible. Preparation consisted of boiling the metal parts in lye to remove the old ordinance enamel finish, degreasing, drying, and spray followed by baking in an open oven.
Several pistols similarly finished are also still good, but the finish quickly wears bright at holster wear contact.
I've also encountered a Gun Kote treated antique Remington rolling block rifle, and had to spend many HOURS laboriously scraping, chipping, and sanding to remove all the finish in preparation for bluing. It's TOUGH!
I can heartily recommend this product for a tough, knockaround gun finish!
John