what do you mean by useless?
it can climb up a road with slight gradient
I saw people played it (the one with a handle bar) in Sentosa Singapore years ago.
HK$70 for 15 minutes, they coached and let you try the basic manuover skills before letting you play.
A bike is a form of transportation and if i can't go 30 or 40 miles with it it is useless to me.
In comparison to a Segway, this thing is inexpensive but i still don't know what to do with it.