I have owned many trucks and have finally found a keeper. When I first got behind the wheel to drive it my first thought was this truck has an engine. Full of power and can pull anything. The interior is put together very nice but it is kind of bland. I am looking at an aftermarket dash dress up kit to spice up the interior. I love the exterior lines of the truck. It stands tall with all the other trucks out there and has a nice throaty sound emitting from the exhaust. The factory tie downs in the bed are pure genius and the most handy thing on the truck when you need it. The only downfall is the fuel mileage, but it's a truck and you're not going to get good gas mileage with any truck.
I can't narrow this down to just one item. I love everything about the Titan. This truck has more power and pull then anything out there except for the Tundra, but thats a $48k truck
The only improvement I see would be a dash kit to dress up the interior. I have heard that the differental case on some of the trucks does need replacing due to a flaw. Talk to you local dealorship as some will replace it at no charge as it is a known problem.