The Cowboy solvent really works taking the fouling from the Black Horn and other powders out of the barrel. Is it better then say, Butch's Bore Shine.. Hoppe's... well it is as good. The Bore Conditioner seems to work real well. But it is nothing more then a very refined oil. Their gun oil seems like a very good quality gun oil.
I took some barrel parts and tested them against other oils like Bore Butter, Birchwood Casey Sheath, Breakfree CLP, and WD-40 . All of them worked equally well. All the samples were cleaned, treated, and placed in a container with wet paper towel and sealed in a very humid environment. This would make sure if there was a chance for it to rust, it would. Now no one would keep their guns (at least we hope not) in such an environment. But all of the samples did not rust.
So if your looking for a good cleaning process, the Montana X-treme is a good way to go. Follow the directions and your rifles will be kept in top condition. BUT if you are going to shoot black powder, take some alcohol and get that stuff out of the barrel. I had some extreme fouling when using Black Powder. I can not say for 100% certain that the Montana X-treme caused the extreme fouling with black powder. But I suspect any new thing I add to the mix.
In the inline rifles that shoot sub powders, this stuff worked very well.