I would sure have liked some paper over powder cup wads when I was shooting BP shotshells extensively. I used them extensively many decades ago. I did finally get a nice old hammer double with totally original forcing cone and bore dimensions, such that standard diameter card and fiber wads resulted in excellent patterns. But, most old hammer doubles I found had reamed bores, etc. that were too large in ID for card and fiber wads to seal nicely.

Niklas