The 3 lever is the key thing that I needed, to tilt the chair angle. Doing that has helped open up my hips a bit, which has helped reduce my lower back tightness. My posture has helped a lot after getting this.
So out of the cheap 3 lever desk chairs, this one is very good for the price.
Building the chair was easy. The instructions weren't overly helpful but I was able to figure it out.

I have only just bought this, after trying other chairs in the store, so I may provide a longer term update. Firstly, don't listen to all of the negative reviews, yes the instructions are sparse, but it all goes together well enough. And there are three levers (height, back angle, and seat angle) plus one knob to fix the back height. They all work and do something!! This felt most like my 'formway be' chair from the office.

No back support very poor quality chair. Waste of money.

I would not recommend. The back does not leaver forward enough to provide back support. very poor chair.

There was a part in the box that isn't on the diagram. Had to use a hammer to get the wheels on and the lever on the left doesn't actually do anything. Diagram that came with it doesn't show the instructions clearly. I got it together finally, but the cones on the bottom are loose.

Purchased this chair today , Perfect comfort and lots of adjustments , Very happy with my purchase

Padding is too firm and the back rest cant be adjusted enough to bring forward for you to be sitting in an ergonomic position, the closest position still causes you to be leaning back. I have had to substitute this by placing a cushion between my back and the chair back to support the gap.

This chair gives me a sore back after about 2 hours.

Wonderful Support - didnt realise what i had been missing in comfort

Very comfortable and easy to adjust