Changing little from the concept version, the production RDX has been unveiled at the Chicago Auto Show.Following the concept\'s unveiling at Detroit, the production version of the RDX has officially debuted at Chicago. Changing little from the concept, the second-generation of the compact crossover retains the basic size of its predecessor while benefitting from more power, better fuel efficiency, improved suspension and a new lick of paint and fresh set of wheels.The previous generation\'s turbocharged four has been replaced by Honda\'s 3.5-liter V6 engine that generates 273hp.