Confused - display audio vs Nav radio

I am a little confused. I have been scouring for information on how to update the maps in my PiP with the 6.1" "display audio" with the GPS mapping navigation feature. I see there is another more advanced radio head with the 7.x" display and the Nav button.

What's the difference? My maps app provides turn-by-turn voice prompted routing, etc etc. What does the other do in terms of navigation that mine does not? Are there separate mapping updates for these two units (display audio with maps, and the Nav radio)?

Also, can I update the maps on my display audio with maps (navigation) and if so, how and for how much? Or, since it's one of the Apps, will it update itself and the mapping data through my cellular data connection?

The two different higher level audio systems both with navigation is a bit confusing to me, so I'd like to get some clarification.

~Dave

 

found some of my answers, but is it true the maps can only be updated by the dealer?

 

I've given the onboard navigation some testing, and until last night thought it was OK (not great). Last night I put it to a test. I have dynamic re-routing enabled. Leaving work, I set Home as my destination, knowing I was going to take a different route than the GPS calculated.

Long story short, as I proceeded on the different route, the GPS unit kept trying to route me back to the other road, instead of calculating a route on the road I was on that led to my destination.

For those in the bay area CA this will make more sense:

I commute from San Ramon to Berkeley and back. Normally I take 80->580 to get home, which was the route calculated. Due to a major accident I re-routed down 880->237->580. The GPS unit kept trying to get me to go on a surface street and circle back around to take 580 through Oakland (which was a nightmare last night). It just seemed wrong that it kept trying to route me back to 580.

Perhaps that was by mileage still the shortest route, but it would not have been the fastest. Last night on the road was a loss anyway - 2 hours to drive 31 miles...

Thanks also for the info on the map updates. Since my iPhone does a much better job, I'll probably get a holder for it so I can use that instead.

 

Can see that happening. In my younger days, before getting into IT work, I drove 18 wheelers into NYC, the Bronx and Manhattan. Can get lost real easy, this was before GPS receivers.

Even with the bad commute, car said it got 52 mpg last night. Love my Prius!