I really don't understand folks' fascination with Pyrodex, and why they use nearly any excuse to justify its use. I honestly can't think of any positive to using it over black powder.
Black powder is readily available with just the slightest hint of forethought. No, you can't just hop in the truck and run to the nearest WallyMart to pick up a pound if you run out. But any of the mail-order vendors will have it delivered to your door within a few days. Bought by the case, it's much cheaper than any of the fake powders. And since BP won't degrade over time, I see no reason to buy a smaller lot, unless you have to deal with storage restrictions.
I have a barrel upstairs from an in*#$& that was given to my father. It previously belonged to my uncle, so I know a bit about its history. It was fed nothing but Pyrodex, but only shot once or twice a year. The last time he shot it (last deer season), he did a quick clean-up, not as thorough as he should have. I've never seen a barrel in as bad of shape as this one is now. I wouldn't even trust the barrel with a light load, as the pitting is so bad that there are half-inch long areas where the rifling is completely gone.
If you're happy with shooting Pyrodex out of your plastic-stocked, stainless "flintlock", even though you've said yourself that hangfires are the norm, then so be it. I prefer a powder that provides nearly instantaneous ignition when I pull the trigger.