If the Navigation is not updated (re: software), it doesn't matter if it's handheld or integrated it would be worthless. Certainly if Toyota fails to upgrade the data periodically, the Navigation would be useless. I can see how that would lead to greater depreciation.

I have no regrets regarding the Nav in my car. Considering it just happened to have everything else that I wanted, I didn't care either way (if it had Nav or even if it were a hybrid).

TCH 50th Anniversary Edition