When I found this, I was really excited to find something almost perfect for my standing desk. I looked at the measurements, to be sure it was tall enough, as I am 6'3". The numbers said that it would meet me at full height. When it got here, I hadn't realized exactly how much of a bonus the extra balance board is. It really magnifies the micro-movement benefits of the stool.
But I first have to mention that the "pivoting column" with the "auto return" does not accurately describe the post column system. The base has a solid but flexible connection to the column that allow it to be leaned in all directions, with a generous range of motion. The amount of activity, that your lower body can be involved in while your torso remains in correct relation to a tall work space, makes for a very dynamic sitting/leaning/balancing combo. The feature should really be touted much more than it is.
What I didn't know about, nor could anyone really predict, how the center shock would react to my weight. It compresses to an inch lower than I really wanted, when I put my full weight on it, with my feet on the balance board. My knees bend more than I care to, and I don't feel I can put the right amount of weight on the board, while sitting. A person with a shorter inseam (mine's about 33") or a lighter build (225 lbs)
I will likely solve this by building a 3/4" - 1 1/2" pad to add to the base, allowing me to actually lower the post a bit. That should really set this chair to be "The One." For now, there has never been a chair to come this close to answering prayers.
I'd purchase again, especially if the base were made taller.