For their SIHH preview, Roger Dubuis, the brand known for innovative materials used on sporty and skeletonized watches, announced two new timepieces – the Roger Dubuis Excalibur Spider Pirelli and the Excalibur Aventador S. Both watches further extend the Excalibur line, stay true to the brand’s penchant for skeletonization, and further the brand’s new relationship with…