I know a bit about it, or at least the Australian version.
It does use gasoline as well, as it is not fully electric. The electric motor powers the car at speeds below 50-60 kph, and at higher speeds the regular engine kicks in as well. Apparently it changes very smoothly between using both engines and just the electric one, you hardly notice it. Not sure about its top speed, but it can go well over the speed limit, it's basically on the same level as most standard cars in that respect. A six-hour trip should be no problem.
I think they're all 4-door cars. Never seen a 2-door version.
Apparently the new model has a solar-powered sunroof, which sounds pretty cool.
If you're looking for good economy and environmental credentials, there could be more vehicle options coming out in the next two years, as electric vehicle technology improves.