Extremely comfortable and durable. This is actually the second chair I got of this kind - I re-purchased because the first one had worn down after over 3 years of use (pretty good life for a home-office chair). The back mesh is extremely durable and holds up to my cat clawing at it like a scratch pad without any signs of damage. The controls for height adjustment lean control and seat tilt are easily the best for the pricepoint (all others only have height control and a simple lock/unlock for back tilt). I highly recommend.
The high points are the comfort of the chair and very good lumbar support (I seat in this chair for work about 12 hours a day) and the price. The low point for me is the range of height adjustment (I wish it adjusted 1-2" higher from max height).
I had bought one of these chairs a few years ago but when I moved was not able to bring it with me. I bought a replacement a few months ago - find the chair overall very comfortable infinitely adjustable - only negative is that the fabric on the seat is more scratchy feeling than I remember my old one was.
Comfy chair things get stuck under the mesh and aren't too easy to get out but other than that (which is no big deal really) the chair does what it should so far.