I got this chair from Amazon in May 2012. I was happy with it for about a year, but now (April 2012) I am looking to replace it.
The good: The price is relatively cheap, it is easy to assemble, it feels sturdy, and it is very nice to seat on when new. My chair never developed any mechanical problem, all adjustments worked well as described.
The bad: The seat cushioning wears off fast. The first 3 months or so was perfect, but then it started to lose cushioning support. 1 year now, and it feels like I seat directly on some piece of wood: it is really a pain in the xxx.