I had 2 lug nut covers and a wheel weight fly off at excessiv--- cough! highway speeds...I'd check those for looseness, fingertight is sufficient...
Rocker panel damage seems to be the most common, look for cracks under the car on the body closest to the tires.
Also, look for scratches on common areas, belt buckle scratces on rear deck, top of front and rear "bulges". Check emblems, heard of a guy getting one with the ends of the flags broken off from the dealer wash.
Yank parking brake firmly a few times with button depressed, if it pops, have em fix it.
When you get it home, remove the wheel lock key from the car, put it somewhere safe. You have no need for it on the road anyway...
Be sure to get all the goodies, manual with Z06 cover, tire gauge, and pen/notepad and video.
Oh, the most important thing. Check on DIC buttons. If it says GAGES, demand that the dealer replace the cluster....ahh, just pulling your leg on that one /phpBB/images/smiles/icon_biggrin.gif But it is one of the great mysteries of C5 ownership.
JC