The chairs sit very comfortably and are elegant.  The only thing I have to look into is the gliding system makes a screeching noise when in use.  The hardware does seem to be not as durable, engineered as it should for the weight, those thin brackets and small bushing do take a heavy load. "I'm a heavy guy"!  I am going to try lithium or silicone grease in the plastic joints to see if that aids for the motion and longevity.