I currently have mine on my headache rack. On my older truck I had them under the bumper. The pics of the fog lights in the rear bumper are "tight" Very sweet. From my experience, the ones under my bumper were better for backing up because they lit up everything I needed to see for backing. The ones on my headache rack are great for lighting up an area to see while working, and are "okay" for backing up. My tailgate blocks a lot of light, and I can't see the ground very well. I will soon have lights under the bumper again. I like those Defiant lights and brackets. Nice.
One more thing. I need to re-wire my setup. When the lights are switched on, they are pretty bright. When I switch them to come on with the reverse, either I didn't use the right relay or else I didn't use a heavy enough wire (more likely) and they aren't as bright. I need to go back in and fix it. So make sure you are using a MINIMUM of 14 gage wire, and if you have more than 8-10 feet, better use 10- or 12 gage.