Hey I got one of those in my Tundra too!
The only gripe I had with it was that my iPod would keep playing even after I turned off the ignition. Well, after snooping around on apple and alpine forums, I found that there was a solution. Alpine sent me a patch cable that fixed the issue...
I love this HU. It was very simple to install, Alpine makes it so easy. All of their color coding matched up with the Toyota harness color coding. Blew me away when I saw that...
Here are a few of the features:
external subwoofer level adjust
treble, bass, balance, fade adjust
internal amplifier on/off (mine is off since I have external amps)
manual txt scrolling (stops the album/artist txt from scrolling on & on & on)
biolight brightness adjust