I dont want to stir up a "hornet's nest" on here but i agree with F.T.B, if you are an experienced/proffesional stalker,your rifle is zeroed correctly,and you are capable of the shot then head or neck shot's are fine,if someone isnt happy or confident to do that then heart/lung is the one for them! if you use feildcraft and stalk to your beast properly you should be able to place your bullet exactly where you want it,therefore being as humane as poss!