I guess it probably depends on how tight the blade fits in the sheath. The sheath I got from Rainwalker only clamps down tightly around the grip, not on the blade, so it hasn't really hurt the finish on my Yard Guard. But if the guy made it to fit tightly on the blade, like the sheath I checked out at the Indy 1500 last weekend (custom kydex sheath maker--makes them while you wait)I imagine it could probably wear the finish off pretty quickly. I didn't buy a sheath at the show.