Longer active time in the field due to only needing battery for control and sensing, while using the built-in nervous system and locomotion.

A few billion years of evolution behind the machinery.

wondering this as well - the article suggests that it would be able to run for longer thanks to the vision/sensory systems being driven by a very low wattage system, requiring a much smaller battery... but I'm not convinced that a slightly larger system, perhaps with wheels or the ability to jump, would be outpaced by this particular "biohybrid"

cockroach is probably easier to grow.

A robot would require extra sensors and thousands of extra lines of code. With this technique, the victims' screams will alert rescuers to their position.