I just received this chair. Delivered right on time.  It is beautiful and sits comfortably.  I am at my desk most of the day on the computer, in between household and family chores, and also evenings watching TV on the monitor.
A screwdriver (manual and power screwdriver) were all we needed to put it together... only problem 2 screws were cross-threaded but the other 2 seem to hold the mechanism firm on the bottom of the seat cushion. This is the only reason I gave it 4 stars instead of 5.  I like that you can order replacements if needed, so keep your papers with Model # and Inv. #. 
The parts were well packaged which was a good thing since the box itself appeared handled a bit rough but all was well on the inside.  I am happy with this purchase.