i have installed the pre-rooted 800x480 - 3GB data partition image and i need to say it's awesome! Thanks to everybody who made this happen!!!
I really like the new launcher and the radio app is gorgeous. RDS is working even better now and showing more text.
Sound has also improved, at least to me. With 4.4.2 it's also possible to install Navigon straight from the play store.
But i have also noticed two things. Number one is, you can't rearrange this five stock apps on the home screen and second has something to do with the XposedMTC. If you set a third party player as default and also set a "Mode" button on your SWC and you click through all modes, your headunit will go into this bootloop screen.
For all people that would like to have an easy way to adjust screen brightness, download "Gravity Box"(Xposed Framework is required) and set the option "status bar brightness control". Now you can adjust brightness by sliding to the left or right on your statusbar. Just make sure to deactivate dimming control in your XposedMTC modul. Also a nice feature is to disable the full screen keyboard. This will make it easier to search for address in your navi app for example. There are a lot of other tweaks that are maybe useful for someone. Definitely worth trying