1 screw did not line up and the guy who put it together wanted to throw it away, the screw (not the chair). I sit in it all day long, and would like to take the arms off, but then it would look less like an "office chair" and my business is very conscious of this atmosphere. I used to sit on just a ball, and felt more freedom and core strenghtening. The chair is a decent substitute, but I'd rather be on a ball. Hope this helps. I also, went with this chair as opposed to the generic thinking it would be more structurally sound, and unfortunately I think it is within the same grade. Personally, I would rather have a different heavier model.