Google Maps vs iGo My Way and Navigon - which do you prefer?

Learning about the renewal of the partnership between Google and Apple regarding the use of Google Maps in iOS 5, I was a little disappointed by the fact that Apple will not implement a proprietary navigation system in the new operating system. I was expecting an offline system with turn-by-turn navigation that would allow us to use the application without having an active Internet connection all the time as it is now in the Maps application. Unfortunately, we stay with Maps and remain connected to the Internet connection, which must be active as long as the Maps application is open.

I know that Google Maps proved to have slightly more detailed maps than iGo or Navigon under certain conditions, but the lack of offline maps and the lack of a turn-by-turn navigation system make it impossible to use Google Maps in certain situations. iGo and Navigon have quite high prices, but the alternative available in iOS lacks some functions that Google offers for free to Android owners at the moment. I for one would prefer that Apple make a Maps application where we can download a map of Romania that we can use anywhere without problems even without a turn-by-turn navigation system. Of course, there is the possibility to download pieces of the maps at various levels of detail, but if you arrive in an area with no signal or with a weak signal, then Google Maps becomes more than useless.

I use Google Maps in the city because Iasi is very well detailed and I don't use navigation systems so much that I spend €15 on iGo or Navigon. Which GPS navigation system do you prefer?