My nav setup just arrived, a Mitac Mio 168 PDA GPS. Came with car kit (gooseneck suction mount & cig. lighter adaptor)
Preliminary testing: works really sweet !! Wife-o's car has the Lexus nav. system (the gold standard) you could buy three of these gizmo's for what her system cost. Nav software included, GPS built-in. USA is 7 maps - roughly 1/2 dozen states per map, maps are under 256MB ea.
It does turn-by-turn, visual and voice prompts, address, POI, all in living color. Ordered an extra memory card approx. $50 so I can load up extra maps.
Now if I can get it to find the car keys.....