The July 2013 Cali brochure states under factory fitted options that the reversing camera/parking sensor combination requires satnav systems RNS 315 or 510 to be fitted. Does anyone have experience of the Kenwood system, advertised in the brochure as a dealer add on alternative to RNS 315 or 510? Also whether the Kenwood can be linked to a reversing camera that would presumably have to be dealer rather than factory fitted? Will be grateful for any feedback. Doug.