I kept debating on purchasing this chair. I am so glad I finally did it. What a difference this has made for my home office. I suffer from degeneration and arthritis in my neck and this has made a huge difference.
For reference I am 6'1". I bought the Dexley over the Hyken for its larger size thinking it would work for my height but the bottom of the headrest rests against the top of my shoulders. The lumbar support at its highest setting is still an inch or two too low and puts pressure on my lower back instead of providing lumbar support.
I was looking at an Aeron chair and had one at a former office space....but too spendy. This is really great comfortable very adjustable and went together easily! I'm tall and thin was worried it might be good for my form factor but it is fine.
This chair is comfortable nice armrests and the mesh is nice but the headrest is completely useless when sitting up. It only adjusts up and down not forward/back. I had a pillow from my old chair that I am trying to use to close the significant gap. Not sure what the purpose of it is unless you're leaning back and looking at the ceiling? Going to give it a try but I might have to return it.