A problem I had while driving on ChongMing Island, just outside of Shanghai, less than a year ago was that although maps in Google Maps was great, unfortunately many of the roads where not built in the south part of island by then. So ended up at lots of dead ends and huge construction sites.

Not saying AutoNavi is better in that regard, but will give more testing. From my limited testing though it seemed to handle searches in Chinese a tad better (hopefully).