While these were the rage aroud here for a while, the experience of a few years is that they have a very high "false positive" defective ticket rate. Meaning citations are mailed and fines assessed for provably innocent car owners. In NYS since the driver can't be identified, only the car can be cited, so it's treated the same way (legally) as a parking violation. Even then many plates are read poorly (provably wrong, when the photos are compared to the registered car), so many of these are being removed.

Where I live, the police know which stop signs and red lights are ignored, and work it the old fashioned way with a spotter car hidden around the corner, and the ticket issued 1/4 mile up the road. Since it's the driver, not the car cited, this is a moving violation, which has more impact.