I am also installing a slightly more elaborate system in the next couple of weeks. It includes a backup camera and a screen for it built into the rearview mirror. The alarm as well as the picture and a digital readout of the distance to each sensor is displayed on the screen in the mirror. When not in use you can shut off the screen and it looks like a regular mirror. It also keeps the compass and temperature sensor from the stock install. I got it from
www.bettersource.com. They had a special through February for $519. I think
www.autobarn.com has the same thing for $795 now.