A long time reader... not much for posting.  I have one question:  Comparing 440C vs ATS-34 vs D2 - how do the three types of steel compare to each other?  I suspect they are more alike than different.  For instance, the key areas for survival are:  (1) Maintaining an edge, (2) able to sharpening, (3) rust resistance, (4) durability, (5) stress resistence.