Pyrodex has its lovers and its haters. If you search out the opinions they are about 50/50. There is evidence of a danger of etching your bore if you don't take special care to clean out Pyrodex residue, and if you leave your gun too long fouled with blackpowder, you can get rust and pitting as well because burnt blackpowder is very hydroscopic, meaning it draws moisture to itself and the salts are not good for metals. Yes, there are plenty of folks that "poo poo" the very idea that Pyrodex is not the bees knees, because they love Pyrodex for whatever reason. There is exactly no benefit for me to use ANY substitute as none of them work well with a flintlock ignition. I do know for a fact that Black Powder DOES work quite well in both percussion and flint and has done so in the case of flint, for about 400 years. BP can be hard to find locally. It is available in multiple places online, and is readily available at local events. Blackpowder is easy to clean--often easier than smokeless in my experience. Its just dirty and smelly and then there is the issue of using water in your bore that scares folk who are not as experienced in the hobby. If you like Pyrodex or 777 or any of the others and they work for ya, then good on you, and good for the makers of substitute powders. I'd use it too if it would work because truthfully, yes, it is easily available right off the shelf. For me, the only practical and viable choice is blackpowder. So that is what I use.