I have never been able to bring myself to try it. I can't understand why they chose that name for it. Surely they didn't know that definition of the word:
Wen - a benign encysted tumor of the skin, esp. on the scalp, containing sebaceous matter; a sebaceous cyst.
However, I do have a friend who reviews beauty products for a blog and she did use it for a while after hearing good things about it. She complained the whole time about how greasy her hair felt and she finally gave up on it.