I have $100 in on it too. Now reconsidering my vehicle needs, I don't see me purchasing one if it ever gets to market.
I really don't believe it is a scam. I think it is an incredible effort that they may not have fully realized and underestimated the time and capital investment to get running. If it was really a scam, I don't think they would have put the effort to design an engine into it.
It's a neat idea. I may still buy one if the target price is met, who knows. We'll see how my screw around cash is doing at that time. Kind of hard to beat the potential of 80mpg when you drive 115 miles/day, but see the math below.
I also bet that Kira is correct, low fuel cost is going to hurt this effort. I bet their reservation intake has slowed dramatically with the recent drop in fuel costs. I did their fuel cost saver calculator and right now based on my current vehicle getting an average of 34mpg (hand calculated by me on every fill up), cost of gas is $1.59/gallon and driving 29000 miles per year, I will only save about $600 per year. When gas is $4/gallon that goes up to $1500 per year. $600 per year to have a dedicated commuter car that I can't carry my two (and one on the way) kids in at the same time, so I would need another "weekend" vehicle of sorts. Or I just go buy a Ford Focus hatchback, normal engine, 5speed and get 36mpg for under $20k or even a SE ecoboost for only $500 more to get 40mpg/6speed and still be under $20k
I hope the best for them, it would be pretty cool to see it succeed.