Well, either they’re both #2 in size, or they’re not, and one or both are not to spec. There’s decades of evidence, science, and physics that show that (all else being equal), the heavier (for diameter), spherical projectile penetrates more on game. Most duck hunters have comprehended this since the 80’s. Higher initial velocity only helps steel inside 30-40.....so I could see some similarity at short range, if that’s the only place you’re using it. I’d still pick copper plated lead #4s over #2 steel, for just about anything I was allowed to.