That thing doesn't look very ergonomic. Check out the new chairs from Steelcase:
http://www.steelcase.com/na/think_products.aspx?f=11871
http://www.steelcase.com/na/leap_products.aspx?f=11872
These are designed to be ultra ergonomic, and adjust as you shift position in the chair. They're also the first chairs designed to be true cradle to cradle products... fully recyclable and enviro friendly.
Even the top of the line work lounge
http://www.steelcase.com/na/leap_wor...s.aspx?f=11873
is only $2000.