Got my polished with blue filters Injen from the Gravity group buy installed today. I'll get pictures after I get a few more mods completed.
It went well although it took me around 2 hours. My kit was not missing any pieces as a few have mentioned. I was a little stumped when on the bottom of one page the directions were telling me to remove a headlight bolt that I couldn't find, then I figured out the instructions had separate 335 vs 135 portions. It could have been marked better. It also should mention that you have to drill the factory scoop to get the new bolt through. I also think it should come with some nuts and bolts to reinstall the passenger side scoop. I fixed this omission myself.
I couldn't really tell any significant sound difference, which was good to me.