AIM7 and AIM120, is carried by those capable for just the one serious reason and that is the "fire and forget" portion of the AIM120's discription.
If you are in a fight beyond AIM9 range and you are targeting and then locking up a radar target that is hostile. Then guiding an AIM7 to the kill is so much better if your wingman is in the same area as the target, or alternatally there is a non combatant in the area of the hostile.