The engine options in the US are 1.6 liter inline 4 at 130 hp, or 1.6 liter turbo at 200 hp. There's also a 2.0 liter inline four at 170 hp. All seem to get the same fuel efficiency: about 30 miles per gallon.
I just bought a new car last November, so I considered this one. The 130 hp is waaay underpowered, and by the time you add the turbo to get the power you need, you're at about $24K.
I ended up going with a subaru WRX in a 2.0 liter turbo with 267 horsepower and paid about $26K. Still get about 30 miles per gallon.
But, I really like the looks of the Kia Soul. We call it the Hamster Car due to an advertisement that had human-sized hamsters driving the car, jamming out to the stereo. If I could find it, I'd post it.