I decided to go with an aftermarket unit for much better sound and really nice built-in iPod integration. I thought I'd miss the changer for "emergency tunes" for when I don't have my iPod, but it plays MP3 and even AAC (MP4) files, so I get a lot of music on a single disc. My main concern with with the aftermarket approach was theft, but in hindsight, the benefits clearly outweigh the risk, at least for now.