I'm 5' 8". The chair fits me perfectly. the lumbar adjustment is a nice feature. Even though it doesn't move much I am able to position it properly. I really like that the back is variably adjustable to position it. Sometimes I want the back more relaxed and this feature gets me there.
I just bought the chair. I love it so far. Very easy to assemble by myself. The left arm rest on the chair is having some issues and the chair is pretty tall. I'm 5'11 and sitting down by feet barely lay flat on the ground at the lowest position.