Challenge GT diffuser is seriously one of my favorite mods on my car. Love the length of the fins, and that there are only 2 not 3. Quality of the carbon weave is other-wordly. The whole thing is just elegant in its simplicity.
At the time i got it, I had no clue that it would become such a rare commodity, but I'm glad i picked it up when i did. There is seriously no valid excuse for challenge not to be putting this lip out in full force - if they could make it once, they can make it again.