I've had an all-Campy 9-speed drivetrain since 1999 and the Campy Record chains continue to provide remarkable lifespans of nearly 5000 miles much of the time. And that is generally race or fast-training wattage, various cheap lubes most of the time, and rain, grit, road snot that's not often cleaned off.
Nice that one of the few things Campy still offers is their Record/Chorus 9sp chainrings. Now if they could only offer all their 9sp component parts...