Wow I had the complete opposite experience.
My Appradio works great. If wired correctly it stops the music and all apps on the iPhone when I turn my vehicle off. I ran a parking brake bypass switch and can operate all functions of the unit while driving.(not that I do, but it is much nicer then pumping the parking brake three times) If your vehicle is turned off for less then 5 mins the unit starts right back up(without boot up sequence) right where you left off on any app ie. Pandora, GPS navigation, iPod. If the vehicle has been off for longer it goes through the boot up sequence but still starts right where you left. The only time it doesn't do all this is when you have switched apps at the phone, but using multitasking I just switch right back to Pandora and it starts right where I left it, same song in the same spot. Backup camera works great.(spend the extra couple of dollars and get a good camera, I found mine for $86) The best part is that the unit is upgradeable. When I talked to the Pioneer reps and addressed a couple things they told me that they were looking into them and others and that a firmware update should be fixing any bugs. In fact they told me to call or email about anything I might find and that they love hearing from customers(not saying it was you, but you might have been overly zealous, or just talked to someone having a bad day). I would recommend the AppRadio to anyone looking for a head unit that cuts out all the other stuff and lets you use the stuff you like from your iPhone. A unit that has Nav, iPod control, bluetooth, video, touch screen, and use of some great apps like pandora all without a $700+ price tag.
The biggest thing I would like to see fixed is the stupid startup warning. Every time you start the vehicle and the boot up process finishes you have to tap the OK button before the radio starts.