If you like Chinese mustard, you ought to try Russian “gorchitsa”, which stands for mustard in Russian. It’s very spicy, probably on a level of wasabi, which ought to be included too, now that I think of it.
Yes. I was shocked the first time I had real fresh-grated (on a sharkskin grater — TMI?) wasabi. I had expected it to be really hot but unlike its ersatz version, the real thing had only an initial heat, which then faded to reveal a complex of multi-layered flavors and aromas, "nutty" among them.