I would have rated it 5 stars with excellent assembly instructions and well made parts but when I got to the literally last screw to attach headrest screw didn't engage. Blind machined hole for which screw can only be oriented to properly without the headrest.
This chair was relatively easy to assemble- there were only 5 steps and they were clearly marked. The tool to assemble the chair was included but it was difficult to use in some areas. I have literally just started using the chair for 2 days and it is more comfortable than my old chair but I cannot comment on the durability of the material. All I can say is so far so good. I like this chair and the many available adjustments to the height and armrest height.