Mr. Old Man Pied as I like to call him was a WC import from Africa. Pete also has a bunch of WC females who are all up in their teens now. Probably some of the biggest girls I've seen. I do believe that CH babies may have a "few more years" on them since they aren't all inbred, over bred, and have years of different morphs in them.
I think over breeding, inbreeding, and all those genetic combo's do play a roll on how long a snake will live also.