GalleryThe first generation of Mercedes-Benz CLS was unveiled in 2004 and ignited controversial discussions among car enthusiasts regarding the new design - the four-door Coupe. Since then this niche has developed many competitors such as Porsche’s Panamera and Volkswagen’s Passat CC. In 2010 Mercedes-Benz pushed the design envelope even further with a concept car based on a CLS estate version. Fortunately customer reactions were positive and the car got the green light for production. NO AMG VERSION?The final vehicle, the CLS Shooting Break (Mercedes spelling), will be revealed in 2012 and our spies spotted the new model undergoing final testing. Our images show a slightly camouflaged prototype which doesn’t appear to differ too much from the concept car. This means the front and rear will only receive cosmetic changes. Dimensions will roughly stay the same which means a length of about five metres. It also means a relatively large boot, which will offer much more space than the current CLS. The range of available engines won’t differ too much from the four-door CLS which means four and six-cylinder diesel engines as well as six and eight-cylinder petrol units from 150kW to 300kW. Only the 419kW CLS 63 AMG is highly unlikely to be available in the Shooting Break version. The new model is set to debut later in 2012.