i used the green on my rigid 54" rds midnight for the snoball run. it served its purpose, but i took it off when i got back. I felt like it was diffusing a lot of light towards the top of the dashboard and my silver hood, so it kinda messed with foreground/night vision. I have an unused amber one also that I'll try next.
i dont think it was my installation, but it seemed to have a lot of bumpiness and spots. that stuff is thick. you might want to talk to a tint shop and see what they can do if you're just trying to "darken" your lightbar.