When we bought the Vauxhall Mokka for Rachel, it didnt have SatNav built in, so after a bit of research on the internet i found a company that do retro fit navigation that goes in the factory location. They offered free fitting if you drive to Worcester, so i booked the car in and headed over today to get it fitted. The nav is great, the screen is 8 inch so nice and large. The heater controls, bluetooth, DAB, FM radio all work with the existing headunit. I had a reversing camera fitted which really helps. Overall i am really pleased with the DriveAudio system and looks just like the factory one, but for a fraction of the price.