zip,
Some of the other substitutes do not measure out the same. I have a .50 caliber Traditions muzzleloader that I target shoot and deer hunt with and have looked at 2 of the other bp subs. I have not used them, but a local shop has both Cleanshot, and Black Canyon.
www.cleanshot.com is obviously the website for the Cleanshot bp sub, interesting stuff in that they recommend NO bullet lubes or cleanings during shooting. It is a volume substition like pyro. Can't remember the name of the company that makes Black Canyon, but if I remember right it does not measureout the same by volume. I could be wrong, it has been quite a while since I looked at it.
hope this helps,
Bergie