I’m not a fan of them because they have been known to cause accidents in the past from people trying to slow down and not get ticketed. TIL this is bupkiss. I’ve read it so many times I took it for granted. That and it only slows people down in that specific area. You slow down, drive past it, then just speed back up.
I think Europe uses a better system, where you post two cameras on either end of the road you want to regulate the speed of. You take pictures of the license plates and time how long they were in the road for, then divide the distance by time to determine average speed. If that speed is above the legal limit, you look up the plate and they get a ticket in the mail. It’s lower tech because it doesn’t need LiDar, it’s harder to ‘cheat’, and it can be pretty cheap for regulating long stretches of road without exits.