Sensor efficiency should actually be scanner efficiency. You can spot a ship, but you can't scan it until 1 or 2k away, regardless of what scanner you have.
In nebulae, that is. :/
A way a lone a last a loved a long the riverrun, past Eve and Adam's, from swerve of shore to bend of bay,
brings us by a commodius vicus of recirculation back to Howth Castle and Environs.