Folks have used non-stainless pocket knives for a really, really long time. They hold their edge just fine. In my limited experience old carbon steel knives have often held their edges better than when they are new.

Acids and other chemicals cause them to develop a patina over time but if it's not a cooking knife so what? I think a patina makes a knife looked loved, but then I'm a knut! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />