I am curious what others here think. I have always thought that the most difficult variety to get right is the kujaku. You need a proper metalic sheen, that maintains with growth. A good kohaku pattern is required with nice coloration. The matsuba netting just makes a third strike of things that can go wrong. If any of these three things are off...it is generally not a great kujaku.
What do you think as far as difficulty level goes? Which type is very difficult for a breeder to get right?