In the video....two guys walking in a parking lot were trackable by the System.
If you had a Missing Person....it would seem possible to track that individual from the last know time and place with some accuracy.
The example given of following people/vehicles from the location/time of a crime forwards makes sense as does back tracking before the crime occurred. The Back Tracking certainly is something current investigative work often cannot or does not do.
Intelligence gathering is what would be the strong point to this system in my opinion.
The Police Helicopter is too visible for that purpose.
As to Search and Rescue....Active Pursuit....the Helicopter with a FLIR and good FLIR Operator is hard to beat. Been there and done that myself but I understand the weaknesses of that system too.
All of these systems have weaknesses....so it is more a cost/effectiveness issue with the best option being a combination of several but plainly Cost drives what combination could be afforded.