I am super confused too, I think the people that said to go with the OEM NAV made a great point, but a big factor is putting in a back up camera...... right now I am leaning to a Base with Sport then installing the auto dimming rear view mirror and semi upgrade my speakers with the NAV. I went to ABT and they said they can do it all (except the mirrors) for about $1,600, they even said they will make something to hide the unit (not sure how)..... I don't know I am frustrated, but this is not a bad problem to have
