Well, sure we could replace our indash units, but where's the challenge in that? I've already got an easier way to play mp3 tunes in the car ~ I've got a 4GB chip in my cell phone, and with my Motorola Motorokr I can play whatever's stored on my phone through my car stereo via Bluetooth to the Motorokr then via FM to the P117. Very slick & easy, but I'd still like to add a CD changer to my existing system.