When I was in China, I had that in restaurants many times. I would say they tasted like asparagus both in flavor and texture, somewhat milder and more tender.
I was told that in China, they are purposefully infected with the organism so that the stems would swell. As was mentioned above, they are banned in the US because of the infection.
However, I was able to find frozen ones sometime ago in Chinese stores. They were labels as Bamboo shoots.
dcarch