I wanted more than the Garmin. Have one already and the screen is too small, especially when you are navigating in tight spaces or across busy intersections. Looked around and chose the Dynavin DVN-E83. It is a very good unit with a 7" screen and looks OEM. Fits in right where the storage tray was. Installation took a few hours but was relatively simple. Installed the microphone near where the factory one is and the Satnav receiver at the top of the windscreen. You will probably need to get an AUX connector with RCA leads to get all the audio features. It has the abilty to connect to a rear view camera and TV (both extras). Appears to be a well made unit and the price is around US$600+. Only downside is the documentation which is basic and does not include installation instructions. But really, you don't need to be a rocket scientist to figure what goes where. The unit can be found at
http://www.dynavin.com/products/product_dnv_e83.php and there is a useful You Tube Video here
Hope this helps.
Geoff