Smaller BBs will outperform the 8mm BBs regardless of weight, they have less air resistance, are less affected by wind and variable air densities, and are denser. I had some 8mm BBs a few years ago, even the 0.45g felt much lighter than the 0.43g 6mm I compared it to. 8mm DO have a greater surface for lift generation, hop up backspin creates some lift and reduces aerodynamic drag (like a boattail bullet), but those two benefits get cancelled out by all the other cons I posted above.
Hence my asking in the first place.
