This is just a wild guess, but I remember some Dog Fathers having inclusions in the steel that caused some failures. Of course, I have no idea how many had problems, probably few. Maybe the S7 steel Dan was getting wasn't up to Busse standards. But this is just a guess, and I could be completely wrong. After I chopped down some pretty big trees with my Rodent Waki, I quit worrying about the toughness of SR 101. It holds its edge superbly, and I prefer it to SR77.