That's a real mouthful Bob.
I built several guns for a local fellow, who is single, and totally obsessed with shooting his guns. It's what he lives for. Consequently, in a very shot time, he subjects his guns to unbelievable wear. I have replaced frizzens on his Hawken rifle and two of his Tulles three times in the past seven years. In addition, he has complete sets of already fitted replacement parts for each of his guns, as well as fitted, tuned and finished replacement locks for them. He does not want to have to stop shooting because of a worn out or broken part, and he understands that these firearms were never designed to be used as hard as he uses his. In spite of all of the use our rifles and smoothies get, the locks last a very long time. And locks with parts such as Bob Roller makes can be reliably expected to outlast any lock with cast parts. Even so, most of my own guns have modern cast parts locks, and I trust them to work well for a very long time without constant maintenance. I submit that we subject our guns to much more use than folks did in the day. Today's modern locks, speaking of those by reputable firms such as Chambers, are just a marvel, and very inexpensive.