I think I owe it to you guys to explain why I don't like the substitutes, other than the historical accuracy (although I believe that is a valid argument..)
In 1994 I arrived in north Texas and joined a muzzleloader club. I did not know where to find real black powder, so I bought Pyrodex P and then turned up at a muzzleloader skeet shoot. I had my side x side 12 gauge ML shotgun, and hit absolutely nothing. I usually hit at least something with this gun. Since I was new, another member asked to watch me load since he thought something sounded amiss. After watching me load, and being satisfied that I knew what I was doing, he asked me what powder I was using. I sheepishly responded that it was the dreaded "P" word and a smile crossed his face. He said, use my powder, please. I loaded the gun with real black, and shot. Two hits, and more importantly, I could hear the difference in ignition time. Since then, I will not go back.
As for the smell of sulfur, I am binary. Hate the smell of hard boiled eggs, which to me is sulfur, love the smell of black powder and my barrel afterwards. Also love the smell of bore butter, but will not ever use it. Hate the smell of Ballistol.
Aren't we weird???