The Carnivore is the best light out there in my opinion. I have hunted with the Laser Genetics lights in green. Although I did not kill any coyotes with it, I hunted with a person who has. It is harder to hunt predators with a green light but it can be done. They don't always disapear when you hit them with the light as others are saying. Most of the time it's how you are using the light that spooks them.
Any bright light will act as a shield. Don't beleive me then have someone shine different color lights of equal brightness in your eyes at say 30 yards at night while they are standing behind it. Yes, a wide red light is still the best choice however.