For my birthday a couple of weeks ago I wanted to eat sushi and my lovely husband took me to a very nice restaurant in town. We decided to order the fresh wasabi since I had never tried. Our server brought to the table a traditional wasabi grater which was cover in sharkskin. I learned that this helps to release the full flavor of the root. She grated the wasabi in a circular motion until a paste was formed and boy what a difference in flavor! Definitely not as spicy as the regular kind, we usually find in non-traditional Japanese restaurants. That "wasabi" is actually just a mix of horseradish, Chinese mustard, corn starch and green food coloring.
