We just performed a very nice upgrade to a new 2015 Kia Optima.
We installed a Pioneer Rear View camera in the factory location on the trunk lid and the Pioneer AVH-4200NEX in the dash.
We retained their factory steering wheel mounted controls, added not only Sirius-XM Satellite Radio and the ability to watch a DVD, but also Apple Carplay and Android Auto. This keeps them connected to the services they love safely with their eyes on the road and their hands on the wheel!