> How useful will that Nav be when you're broken down in the middle of
nowhere?
> Junk it!

Still pretty useful. it has more than 12 million point of interest including
auto-mechanic shops, police stations, gas stations, tow truck shops and so
on...

Brand-new or years old, any car can break down in the middle of nowhere.
Such probability should not limit you from taking advantage of the wonders
of technology. ;-)