From the NHTSA, I thought the speed restriction interesting. I didn't know that.
"Drivers in the U.S. do not typically operate their vehicles at speeds above 100 mph. Maximum speed limits on U.S. highways range from 55 to 75 mph. Some vehicle manufacturers, e.g., GM and Ford, electronically restrict most of their vehicles top speeds at approximately 106 mph. NHTSA also believes that an upper test speed threshold of 160 km/h (99 mph) ensures a minimum level of safe operation that is 25-30 mph beyond typical speed limits on interstate highways in the U.S."