This was discussed on another forum and I did some quick back of the envelop calculations and I doubt this is a viable technology. They claim in the right conditions the thing can produce 0.8 liters of water in an hour. Even at 100% relative humidity, you would still need to extract around 500 W-hr of energy from the air (not including any inefficiencies in the device). AA batteries have about 1.5 W-hr of energy, so it would take more than 300 AA batteries worth of power to live up to their claim. Additionally, a device like this most likely is using Peltier coolers which are notoriously inefficient. It's a neat idea, but not likely to come to much.