It's a nice idea, I'll give them that. Inasmuch as the future of automobiles is technological diversity, I think there will be a place for their cars in the market. However, I don't know how it compares, energy efficiency-wise, with Battery Electric, which I consider the holy grail of green car technologies. Certainly a BEV is going to perform better and be a lot more pleasant to drive.
From a purely economic standpoint this technology makes a ton of sense. If they can really get them out the door for that little money, they have a huge advantage over your average BEV, whose battery pack probably costs as much or more as one of these vehicles. I'd seriously consider one based simply on price.
However, color me skeptical of those range numbers. I'd have to do some math to be sure (don't have the time or references with me here to do it right now), but I think you'd either need a huge air tank or massive pressures to get that kind of energy storage out of compressed air.
I'm also a little concerned about what happens if that air tank gets punctured in an accident. They'll have to do some serious crash testing to make it safe.
One final concern - what powers the auxiliary systems? (HVAC, stereo, wipers, headlights, etc.)
