I use this chair for work and it is very comfortable. I bought one for my husband to use at home for a gaming chair and he really likes it. The only downfall is that it is not the best for taller people. The headrest hit him right in the shoulders so we decided to just leave it off.
This is a very comfortable chair and great value for the price. I spend around 8 hours a day at the desk and this chair is a huge improvement on my previous one (which admittedly wasn't very good). My only minor complaint is that the arm rests become a bit uncomfortable after a few hours; I'm not sure how to describe it but they sort of rub my arms.
Picked up one of these about 4 years ago and when we needed another one I was thrilled to see that the Hyken was still available. It is quite comfortable for all day sitting and holds up well - The 4 year old chair looks almost identical to the brand new chair! Tip: If you are rolling around on wood floors you may want to pick up casters specifically for wood floors - shouldn't cost more than $10 or so...