I picked the Nav pkg over the sport because personally I go road trips often and get lost plenty
Beside, I did not think I would benefit much from the sport pkg cause I do not push it much. After having the nav. It looks nice but not too smart in my opinion. Very limited option compare to the Pioneer Aviz Z2 I had. Here is my story on my last trip.
I was doing to Oxnard from Sacramento, when a person looking at a map, he would go from I5 then CA126 west. but the Nav pointed me to I5 all the way to 101, then go up north. This is calculated as "shortest time" I did not like the route so I changed it to "shortest distance" It routed me from I5 to some small street for 5 miles then CA126. I bet it is shortest distance but it takes things too literally and lack of human intelligence.
So overall, it works but not as intuitive as human so it can get annoying.