Some years are definitely more desirable... 98 Commander for instance.
Emerson has changed various things on the Commander and most of there other models over the years, handle screw placement, thickness of the liners, type of material for the non locking side, flat head phillips screw, dome head phillips screw, etc.
Most recently the style of pivot was changed and the latest was going from a back spacer to standoffs.
Whenever I sell a Emerson I always list the year of manufacture so the buyer has a better idea of what they are getting.