Black powder does shoot PRB excellent. I used to shoot only black powder. The only cons I can see is it is a lot more dirty then pyrodex. You have to make sure and swab between shots, but you should if you really want to get good groups, no matter what you use. It is a little more of a mess to clean, but cleans up once you learn to clean it with soap and water. The one real con I have is, it is almost impossible to purchase in my area. I have to drive almost 90 miles to get it. So I use Pyrodex or Clean Shot. I did notice that the store had a supply of American Powder Company, but I think that is Clean Shot. I have thought of getting some FFFg black powder and loading down the charge for my .50 caliber with the 1-66 twist, just to see if it makes a difference.