Hello LR308Shooter...
I don't have an answer to your questions, but I was watching this post/thread to see what any response would be as I try to remain open to the experiences of others.
First... I have not used any type of Bore Coating, and I have not had any bore coating applied to any of my firearms. I have read of and asked experienced, inexperienced shooters, both wise and unwise their thoughts and experiences about Bore Coatings... the end result for myself was that this not enough reliable testing and even with that, results claimed would not likely effect my shooting/cleaning habits. I have read a couple of "serious" tests of various bore coatings (like Boron, which makes sense) and some coatings that make little sense.
Therefore, no insult meant to you, and your perceptions AND any actual experiences you may have with Bore Coatings... the end result of my attempted education of the subject was this... EVEN if it did work well, its effects would be so small for my shooting ability, the results would not be detectable. If the claimed effect of bore coatings were 100% as stated, there would be an effect of shooting, as well as cleaning time reduction of which I was no convinced as evidence was too subjective for me.
There is a great deal of very unscientific or completely perception based claims of reduced fouling and reduced cleaning times. I have not seen anything convincing, though I have not looked in a couple of years on line. Of the few seasoned skeptic shooters I know, not one has tried to convince me of the value of bore coatings. I have never really had any issue with leading or any other fouling, but that could be my own perception, choice of ammunition and firearm. With that said, I do buy Hoppes cleaners by the gallon, and but many thousands of rounds down range in many different firearms each year.
Ok... as I stated, I don't really have an answer to your question, but I do have additional response which IS relative to your question being Desert Eagle specific. I have a dozen of so barrels for Desert Eagle pistols. The factory bore finish has varied greatly over the years, and I mean greatly. Think chatter marks to mirrors. The only product I have ever used that I could actually tell a difference in cleaning is a bore polish I randomly tried from Brownells called J-B Bore Bright Finishing Compound. As the product states and the experiences of many persons, for years, it does truly micro-polish a bore. I once tried it on some drill bit for easy inspection specifically to see it effects on sharp edges (as it might effect to sharp rifling) and it must be VERY fine as it does nothing that would concern me. This cleaner/polish does polish some pretty hard materials, but isn't aggressive at all. In the polygon rifling of a Desert Eagle, it does an excellent job of improving the lower quality bore finishes you may find in some barrels.
I suppose this falls into the category of a non-answer. And again if you are a strong believer in results from Bore Finishes, I mean no offense. I am open to being convinced they can be of value at least to others, and maybe not to my shooting habits and level of shooting expertise.
Well, it seems to be open season on paper and steel targets, so I will try to bag a few.
Happy Shootin'
MrBlackCat