you'll be surprised at how fast the ignition is vs pyrodex.
+1 I know I was greatly and pleasantly supprised!
I sure was in my caplock. The real stuff is cheaper, no more or less corrosive, as easy or easier to clean up, and it flat-out out performs any of the substitutes when the name of the game is side-lock muzzleloaders.
Now I've moved on to a flinter, and there is no noticeable difference in ignition speed versus the caplock when using a 4F prime and 3F as a main charge. Reliability is as good or better in fair weather.
I've got a local source for real black, it works great, and it's about $10 cheaper per pound to shoot. I don't see myself switching any time soon.