Although I didn't realise it, I am sitting on one in my office right now. The entire 3 floors are decked out with them, and I can attest to the incredible configurability. It can, however, bite you in the ass if not set up correctly. Read the instructions!
I have a different ergonomic chair, but I just wanted to reiterate your point: Seriously! RTFM! It doesn't seem like something you'd have to do for a frickin' chair, but you'll be so glad you did.
