No. It's called sniping. Why would they give us such a long range weapon if using it from that range was considered "unfair"?. Cheesing a part of the game is going outside the games normal boundaries to finish an objective. Ie: going outside the map with Armor piercing rounds. Or how people used to DC on Crota. Unfair my ass. It's more of an assassination. Staying inside the games boundaries without glitching anything is all fair.