Mostly, I am satisfied with v5, but one thing is really very inconvenient - Car Adapter mode - when ignition is turning on, bootloader loads the original firmware.
It is ironic, since when you need it, original firmware is usually quite hard to load.
Everytime I forget to turn the player on before I turn the car on I have to disconnect the power, turn the player off, turn it on, plug in the power.
I know it was intentionally done to prevent some other bug, but I thought maybe it was addressed in current SVN version.