Just to put the blackpowder subs in context with other forms of ammo.......
Would you buy .30-06 cartridges that go off 95% of the time and only work in 2 or 3 brands of rifles? Also there's no way of knowing if they'll work in your rifle without buying a box, and they cost twice as much?
?On top of this, some are only good for a year or two and then they are no good.