We had Steelcase Think (http://www.steelcase.com/na/think_products.aspx?f=11845) where I used to work. They look fantastic with their mesh back and adjustable armrests, but they're really not that good. The seat cushion isn't adjustable and lots of them broke, they were quite flimsy.

The Leap chair does look a lot more adjustable and maybe more solid too.