With its space-age body, super-efficient powertrain, and laser focus on its urban mission, the i3 pushes the boundaries in automotive design. This tall, narrow, electric city car not only looks like a futuristic personal transportation pod that just drove off the set of the latest "Tron" movie, it's the first widely available car to use lightweight carbon fiber for its basic body structure.
BMW i3 Road Test

With its space-age body, super-efficient powertrain, and laser focus on its urban mission, the i3 pushes the boundaries in automotive design. This tall, narrow, electric city car not only looks like a futuristic personal transportation pod that just drove off the set of the latest "Tron" movie, it's the first widely available car to use lightweight carbon fiber for its basic body structure. That single mission focus however, makes the i3's appeal rather limited. Under the modern vibe, there are some peculiarities that might deter many buyers. 

Since we tested it, the i3 has gotten a larger 42 kWh battery, noted as 120 Ah. BMW claims the electric range exceeds 150 miles. The optional two-cylinder gasoline range extender (REx) acts as an onboard generator that continues to power the electric drive when battery power depletes. It's designed to reduce range anxiety, but as we found in our testing, it's not really supposed to be used as the primary power source. Think of it as a set of training wheels for electric-car newbies. Most i3 buyers are opting for this option.

The 2.4 gallons gas tank helps extend the electric range and alleviates range anxiety but long distance travel requires frequent stops for gas. Note that the i3's gas consumption is no better than low 30s mpg, undermining the car's efficiency if it's not charged frequently. For those unable to charge frequently, a hybrid model that gets 50 mpg all the time is a more practical choice.  

Best Version to Get
We would get an i3 with the range extender. The Deka World should suffice for most potential buyers, but we think the Giga World brings a more attractive interior with nicer upholstery and wood trim. 
Road Test Scores by Trim
4-door hatchback Giga 2-cyl 1-speed Direct
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