Try them in your rifle.
You'll generally get folk saying that the lighter pellets are a tad flatter re trajectory but will drift more in the wind.
I think it's as much to do with pellet stability leaving your barrel. I've put Express ( Mozzies ) through my gun and they've taken less wind than anything else.
A slightly heavier pellet that flies very stable will slow down less at longer ranges so you can end up with virtually the same trajectory.
What rifle are you shooting?
Springers generally are more efficient with lighter pellets so a lot of springermen use the 7.87 rather than the 8.44gr.