Swiss and Old E are best but it really comes down to what you're doing and if your gun "likes" it. I shoot North South Skirmish competition with Civil War era guns. Swiss provides a bit better accuracy only in one of my guns, and it's a tie in the others so I shoot Old E. Think of it as grades and brands of gasoline. If you're serious about competition, you won't shoot reenacting grade powder and yes, there is such a thing suitable only for blanks.