UNLESS you do not have electricity in your home, it would be difficult to avoid Ford’s blanket advertising for the superior-to-Prius average fuel consumption of its new Fiesta Econetic. Relying on a frugal diesel to achieve excellent economy as well as low CO2 figures, the German-built five-door hatch makes for a practical, affordable and enjoyable eco runabout, as well as a stylish one. But is the Econetic really the best Fiesta you can buy?