Ive had this chair for a couple of months now and I love it. The only thing that I would change is the head rest. Like everyone is pointing out it cuts into your neck.
Lumbar support is good. Arm rest adjustment is very good. Tilt control is average. Lift cylinder average. Chair is about 2 inches too low for my taste. I have ordered a taller after market cylinder to attempt to adjust. pending receipt.
I bought this chair after reading multiple reviews online of office chairs meant for comfort during 8+ hour long work days. Unfortunately the width of the seat is such that the plastic was digging into my hips and was incredibly uncomfortable. I will be returning the chair and buying another more expensive chair instead that offers different sizes to accommodate all body sizes.