Personally, I have already paid for Navigon ($99) for navigation so the navigation isn't an issue. Actually if you have the money to blow iPhone has the advantage for cross country trips, if you haven't already bought nav on the iPhone and don't drive cross county google has the HUGE advantage here. Maps are stored on your iPhone (about 2GB) so you don't have to worry about losing a signal and your maps in the middle of no where. I am actually really glad I didn't switch to the droid before I drove from Dallas to Seattle because I was in the middle of no where with no signal when I ran into a highway closed due to weather. No problem with everything stored locally, I would have been screwed with google maps. I realize this is not the case for most people, I just already have the app on iTunes so it's not an issue for me.
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