SatNav: The cheaper and better solution
I have yet to find a built-in car navigation system that can compare with, say, a dedicated TomTom or, even, TomTom running on the iPhone. My car is four years old but the navigation system feels like it ten years old (it probably is, given design lead times). It is clunky and inaccurate. The postcode entry system is useless because it skips the last two characters. British postcodes are accurate to a specific street, so all you need know is a code and a street number. But without the last two characters the destination could cover a wide area in the countryside. A few days ago I had a village name, a house name and postcode but no street. As a result the car's system had me going round in circles until I got out the iPhone and asked TomTom for assistance.
The annoying thing about this is that when my car was new the navigation system, as an optional extra, probably cost a couple of thousand pounds--compared with £100 for a TomTom or less for the app on the iPhone.
Now car manufacturers are beginning to see sense. Honda's 2015 Jazz (Honda Fit in the USA) will allow you to link your phone to the built-in screen so you can use whatever navigation app you choose. All you need is an app costing around £30. This is an ideal solution. It is likely to be the cheapest option and by far the best. It's about time all car manufacturers took heed and stopped foisting out-of-date and sub-standard systems on unwary buyers.