They cost about the same as normal economy cars and they have less room. Is the car really worth getting for 6-8 extra mpg's?

I certainly don't think it's worth 6-8 extra MPG's.

I don't care what kind of safety rating it's got, once it's hit by an SUV, you better hope you make it out alive.

Not to mention these cars are impractical.

These cars will work in Europe or other countries with not much spaces on the road. But, it's just not meant for US.

I wouldn't buy any of them. They're not to my taste, and small cars are notoriously unsafe.