We just bought one those expensive air chairs. There are a few drawbacks though.
Some people have a hard time getting up on it.
I'm not sure why yet. These people are very good at other devices too. Everyone who skis succeeded during our last trip, but for some, it is quite difficult. For me the skurfer was the hardest device to get up on. When we noticed this to be universally true, and started warning people, we had no more problems.