What do you wish for in an "Upgraded" FP ? Mine is 6-years old and works fine.
However, there has bee a problem with some in the recent past. See my post #3 here -> http s://www.rimfirecentral.com/threads/cz457-firing-pin-being-shaved.1328985/?post_id=13765995&nested_view=1&sortby=oldest#post-13765995
