It's 10-20% of the price of a segway, and you can climb stairs, and carry them much more easily. They also look easy to put on (unlike rollerblades).
If they can sell 500 units, they'll easily hit their stretch goals. I think they'll do OK.
They just shouldn't be afraid of being the next segway - segway didn't fail because it was "dorky". pg was using that as an example of the problems companies get when they run fat and are too cloistered. Segway had a lot of other problems (with the same root cause) - it was way too expensive, and it was too awkward outside a controlled environment (both of which these skates seem to solve). It also tried to sell 50,000 units on the first iteration, while these guys are selling maybe 1000 (for the kickstarter), and can then tweak things based on customer feedback.