This is a great office chair. I spend a minimum of eight hours per day in it and it's comfortable throughout the day. The only drawback I've experienced with it is that the cushion for the lumbar support doesn't stay locked so I have to readjust it regularly throughout the day. If not for that I would have given it a five star rating.
The chair is wonderful! super comfortable - the only down fall was that I ordered it in Black and it came in Red. I didn't want to take the extra time to wrap it all back up and send it back so I just kept the red one.
I am hard to please with chairs so take this with a grain of salt. The lumbar support felt like it was hitting me in the kidneys after a while and didn't give good lower lumbar support. The top edge of the chair was very hard on my shoulders if I wanted to stretch my arms up or clasp my hands behind my head. Those were my biggest problems.