actually you can make a carbon for about 150-200. A good one as well.

 

Sorry here's the right link.
Re Amemiya UnderSweep

 

WOW! That is pricey. If it was acturally a molded piece I could maybe paying that price. But not for a flat piece of CF??

 

I made a couple of undertrays out of 0.25" black ABS for the Cwest kit.
I noticed a difference in how the car handles. It seems like it sucks the front end down....
I wish I had this when I had my car painted. It completely stopped all the scrapes and paint nicks. Not to mention keeping your bumper solid going down the freeway.
I would be willing to make them if there were enough people interested.
I'll get some pics tonight.