Just barely below Duke for me.
Duke has better vision and cutting ability. There's that sixth sense people talk about with backs - feeling the flow of defenders in traffic, and being able to anticipate a couple moves ahead. Duke has that. He's a natural in that regard. He's so elite at using his blockers and ******* with a defense, always being one step ahead and creating creases for himself that aren't even there. He's got a grace and smoothness to his game.
Cook looks like someone built him in a lab. He's not as pure of a runner to me, and isn't as elusive in traffic. But he has size and speed that not many do - he has ELITE home run speed. He's a freight train tied to a rocket ship. He's like a greyhound in the starting gate of a race, he just wants to flip the switch and go 100 mph. He doesn't have the fluidity to his running game that Duke does, which is fine, because he'll just blast through the smallest of creases and leave everyone in his wake.