This is for the chair model (ST63145). The lumbar support is awful. After only a few minutes my back is hurting regardless of position. The chair feels sturdy enough. Also, even at it's lowest height the chair still feels like it is too tall. I'm 6 for 2 inches and I felt like it was putting pressure on my legs. I tried numerous adjustments and just can't get comfortable in this chair.
I first bought this chair back in 2020 when I started working from home. At the time, I thought it was pretty reasonably priced at ~$200+tax. I'm in it 5 days a week, 8+ hours a day, and at least for me - a 5'6" female, approx. 200 lbs. - it has been very comfortable, and I'm extremely happy with it. I've had no issues with adjusting the seat height, armrests, or lumbar. I've felt very supported, and having a headrest is a game changer when you need to lean back from your computer for a quick break. The only issues I've had were the foam pad under the front of the seat starting to break and fall out after about 4 years (you can just stuff it back in), and eventually the hydraulic lift for the seat stopped working after 6 years. The chair is so reasonably priced that it's basically not worth repairing it, so I just bought my second version of this chair this week, and it cost LESS than when I bought it 6 years ago! I also tried out the Dexley (along with every other chair in the store), and I still like this one best! The Dexley is very similar, but this chair (the regular version) seems like it fits a shorter person better. My husband ended up buying the Dexley and liking it, but he's 6' tall. For the money, I'm not sure you can get a better chair than this.
Good quality materials, very poor design. Controls to raise and lower chair and recline are finicky and difficult to use. Lumbar support is hard and very aggressive, even on the lowest setting. I find it very uncomfortable and if I sit for more than a few minutes my back hurts. Not what you want in a computer chair.