Great chair overall. Good for tall people. I am 6'6" and this chair is comfortable for me. However, the chair arrived with a back/headrest that did not stay in position. It would just fall rather than staying at the position it was set to. On the positive side, Staples sent a replacement back piece very quickly and it now works as it should.
The lumbar support is terrible. It is like a hard cushion attached to the back on the chair. Not fixed but wiggles. I have sat in this chair 1 afternoon and don't think I can do a full day.
I have been having lower back pain, and my old office chair was making it worse. Not a miracle, but this chair is working. Great office chair - very comfortable. Box is heavy because of the weight of the seat and back - dense foam, it is.