I had one of these until very recently, a first generation CADEX frame (1987, so now a good 35 years old), still as good as new, it went to Germany and is now plying the streets of Berlin.

Unless you smash them up just keep them clean and they seem to last quite long, at least as long as comparable steel or aluminum frames.

The weak points are where aluminum is bonded to the carbon, those spots you need to monitor and if there is any damage at all you should count the frame as lost.