guys, I am looking for invision headrest dvd. Has anyone installed that kind of car dvd before? Which types of invision headrest dvd you've got? Could you pls tell me whether it is very hard to install a headrest dvd by myself? Also need your advice about the invision headrest dvd I plan to buy. 7 inch Digital Car Headrest DVD Player with USB/SD/GAME/IR/FM transmitter. http://www.justcardvd.com/products/7-inch-Digital-Car-Headrest-DVD-Player-with-USB%7B47%7DSD%7B47%7DGAME%7B47%7DIR%7B47%7DFM-transmitter.html