Thanks for everyones replies.
Here is something to think about:
Auto insurance companies fund and or supply police departments with radar guns, not to make sure that everyone is driving at a safe speed, but to generate revenue by increasing your insurance rates dramatically after you get a moving violation. In addition, Police who use speed traps are also not keeping your safety in mind when they are clocking you. They are working on increasing revenue. If they wre concerned about you being safe when driving, they would be in plane sight to remind you to look at your spedo and slow down if necessary.