If police helicopters were just flying around with no particular mission in mind, then I would say it is a waste to have them in the air. They should be deployed for a particular objective and then put back on the ground. The taxpayers deserve some discretion with the way police spend their money. This is not a warzone and we are not the enemy.
I see it as possibly less useful than a helicopter. What do they believe they will accomplish by having this thing aimlessly circling the city? How is spying on citizens going to "keep people safe" as the Police Director says?
Really, a 'copter should be up patrolling (or trolling) already to any bit of good.
In a crisis of any kind when the cops have to put one in the air, they can't 'scramble' like the air force does when a UFO shows up on radar. It takes awhile to do the pre-flight, start-up, systems check, etc. Maybe up to 1/2 hour.
So maybe a shift of UAV's are in the future. It will come at a cost and I know many cities don't have the dough.