Assault rifle, because when you think about it, it takes quite a bit of skill to use also. Whereas the BR can be used at any range, the assault rifle makes it necessary to get up close and personal. That means you have to flank people, surprise people, you can't take conventional routes or go out in the open because of its lack of range. The assault rifle promotes movement around the map, whereas the BR is more of a see someone shoot someone gun.