what's the difference between a xenon air dam and a fiberglass one? Is the xenon made from better materials?

Is the Xenon a urethane air dam? If it is, it's more flexible than a 'glass one, better for cars with low clearance, but the paint tends to crack after awhile from the flexing.

Yes, the Xenon air dam is urethane and will flex rather than cracking like the fiberglass one. The downside is that the urethane air dam is known to flex at higher speeds as well as sag over time. Most people who buy the Xenon part will make a center support out of aluminum to keep the nose from drooping. You will also need to use a flex agent in the paint so that it won't crack if the airdam is flexed during a curb or driveway hit. I plan on going with the Xenon one, myself. I really don't want to repair fiberglass over and over whenever I encounter a steep driveway apron.

let me tell you...

I bought a Xenon Urethane air dam from MSA...

the box was about 12 inches by 30 inches... I was shocked..

they folded that air dam IN HALF about 3 times and shoved it in this box..

I put it out in the sun for an hour and it unfolded and retained its original shape.. i was shocked.. (i speeded it up with the mom's blow dryer)

Ive bumped a few curbs when parking.. and it just flexes.. its AWSOME.

Click on the pic.. I recently added a new lip to it.. so you can see the rivets