I returned it after a week. It was not comfortable and it had a wobble to it that made it feel cheap. Also the hydraulics were faulty and the seat kept lowering overnight. So every day I would need to raise up the seat an inch or two.
There appears to be a bit of a wobble left to right when tilted back slightly but not when the chair is straight up. Otherwise it is comfortable and the upholstery appears better than average.