OK I sometimes saw while playing golden eye source, some guys that are like this options I mentioned,
here are for help you:
option1: if you are surrounded of enemies all the time or if you shoot have more chances to kill your prey.
option2: if you want to kill your enemy easily risking 2 while reloading you will be damaged alot
option3: if you while making teams, you cover you teammate risking to while covering or killing, you can get surprised. (I surprised lots of snipers)
option4: while your teammate distract, you kill without making noise (trust me, if you do this without a distraction, you will be gunned)
option5: if you are not afraid of the death and go with a most powerful gun (golden gun is good option for kamikaze) risking that if you fail you will commite a suicide (if the enemy have a powerfull weapon too)instead of killing your enemy.