It’s not that I’m totally opposed to them, but here’s a fine example of what happens when they get extremely popular. Yes, they are being referred to as a “silent killer” and with good reason. Besides the accidents in which people get killed outright, the fact that some use lead acid batteries makes them far less green than some people would like to think. Add in that even in the US, there are still coal powered electric plants, and they’re just an all around bad idea.
Make them light, safe, affordable, and truly green, then you’ll have my attention.