The air cushion has a few spots, which I can overlook but, since it is not usually visible anyway. Otherwise, the chair looks surprisingly chic. The only drawback: For me it is a little too big. Depending on where I'm sitting, I can not leave my feet completely on the floor. However, I'm really small with just under 1.60 m, so that this issue will play no role for most. I keep the chair in any case anyway.
Some of the exercises I have tried, some I knew already from my gym. The air cushion is a good supplement and can be quickly and easily removed and stowed again.
Conclusion: The chair is ideal for very small people like me, but otherwise very good. In particular, as a bargain so I would buy it again.