I'm impressed that Segway is still not as popular as it could be, its probably so way ahead of its time. It reminds me of when the car first came out.
I've used a Segway on two different occassions and loved it. But they are rather expensive and not very portable in an average car. The alternative I prefer is an electric scooter by GoPed. This is not the cheap Chinese ones like one might see, but a proper off road capable one, made in USA, with Lithium Ion models capable of a range as much as 24 miles. And yet small enough to pick up and carry in the trunk of most any car (except my Miata
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The Segway has the advantage of being able to stand still of course, but the wheel base being wider than your body does make manuvering thru crowds problematic. On the GoPed, your effective width is the same as it normally would be. FWIW, GoPed also offers gasoline and propane models....but the electrics are so quiet I prefer that.