While ED-E or its copy is in your party, your detection radius is greatly increased (equivalent of having a full 10 in Perception) by substitution ED-E's detection for your own. It also allows you to target cloaked enemies in V.A.T.S. mode and grants bonus to hitting that target in V.A.T.S.. When paired with the Spotter perk given by Craig Boone, the player can effectively snipe targets from much greater distances.
- This perk's effectiveness is limited indoors, since walls and different floors will prevent you from accurately assessing the location of any hostile targets. It will, however, give you a general idea of the numbers you'll be facing. Outdoors, on the other hand, it can allow you to perceive and bypass particularly dangerous foes without drawing their attention. It is possible to learn to identify some particularly dangerous enemies by their movement patterns. In particular, a closely packed group of 4-6 fast-moving enemies is almost certainly a nest of dangerous cazadores.