It has a little more power and MP3/WMA CD playback, a couple more tone options for tweaking, and I think, better bass through the original front 6.5mm speakers which I'm about to replace to complete the installation. Plus pre-outs for hanging sub-woofers off.
I loose the integrated look of the original, and increase the risk of my car getting busted into, and the display is not as easy to read in daylight.. But I prefer the JVC musically, it's a nice unit, although not so cheap when you have to buy the fascia adaptor and the antenna connector..