I have not personally shot them, because my rifle is designed for shooting ONLY Round Balls. However, the Ballettes, are designed to be used in 1:48 to 1:66 ROT barrels, which are often sold to shoot RBs. They work well. They are not needed nor desired for deer hunting. But, if you are likely to hunt Black Bear, or Wild Boar, they make a better choice of projectile to use to penetrate heavy hide and body tissue. If you hunt Elk, and think its more likely that you will have to shoot through a shoulder bone, the ballette is a better choice than any round ball of similar caliber.
However, if you only shoot round balls, and want more penetration, you can cast balls from Wheel Weights, or other lead alloys and get a harder ball that will mushroom less, but penetrate further than a pure lead ball will.
Welcome to the forum. :thumbsup: