There are different versions of a kneeling chair. This is the original and is also more expensive. For years, I have had an inexpensive metal version with rollers, and it has been great. It was important in getting me past some lower back pain. But the original version, which I bought recently, is wonderful and has good qualities the others do not. It is on rockers (like some but not all other versions). It is made of very strong plywood and very flexible. So when you sit in it, your body can adjust your posture in subtle ways all the time. In particular your lower legs and knees are not locked into a single fixed position. Changing posture as you work is very healthy! It's also really beautiful and super easy to assemble. I think if you can afford this version it is definitely worth it. If you want to spend less, you can get many of the posture advantages of a kneeling chair from other versions.