Given the rate of change and improvement in mapping, interfaces, etc. I wouldn't feel that Garmin/TomTom, etc. are the poor relation options. I have factory nav in the e39 and while it works fine, graphics quality, entering destinations, finding POI's, ETA calculations, etc. are all a bit clunky and slow compared to even a low end Garmin or TomTom. With these, if they can't be upgraded further then at least they are low cost to replace.