Satellite navigation, should i go for a pda+software or a specific device?

what are the advantages of each, it would seem better to have a pda installed with software as you can get more out of it, however your advice is welcomed|||If you're worried about portability (the ability to use it outside of your vehicle), I would go with the PDA. If you are going to use it strictly with your vehicle, I would go with a dedicated navigation unit (like the Pioneer AVIC-N2). Both have decent benefits, the major difference being the portability. Though, a dedicated unit in your vehicle will give you slightly more options and a much larger, more readable display.