Here in Ecuador we're lucky, there are not many hybrids and a lot of the seeds are "samenfest". With cabbage like plants the problem is that they cross-pollinate with so many other varieties that it's very unlikely to get the same type out of it.

Good to know that the cabbage is normally like that. I had a Napa Cabbage (Chinakohl) that worked, too, I have some seeds. Haven't tried them, though, that I have to see. I need some good earth for that.