Pretty comfortable. My only complaint and its a big one is its impossible to lean back. Unless I grip onto something and push really hard and then I have to keep my feet raised on the desk. Theres no way to use your feet or your own body weight to push the seat back. And even once back it only stays there if like I said I hold onto something other than the chair. And yes I have the knob loosened all the way to allow full leaning. Imagine an airplane seat with slightly more padding that only reclines about a half an inch. thats what this feels like.
Looks nice. Easy to assemble. However for me it is uncomfortable. The seat is hard. The height does not adjust low enough. The lower back support in non-existent. The chair I sat in at the store did not have these issues.
The chair was easy to assemble and is relatively comfortable; just a bit hard but overall not bad. Only If the chair was ergonomic it would be icing on the cake.