I'm pretty sure the holes were drilled backwards the controls are in the back right instead of the front left as the photos show. But it's still comfortable pretty ergonomical for me. I work 9 to 10 hours a day and I feel good at the end of the day!
The chair is not bad for the sale price I got it for. It was easy to assemble. It is reasonably comfortable. There is a slight wobble in the seat when I first sit in it but it seems to be stable once I'm seated. If you are a big person you might want to think about getting a oversized chair.