What is a good car for a cross country road trip?

I'm a 17 year old male and in high school (graduating ths year). I'm planning on going to college in California. I am from NY. I currently have a pickup truck. I'm looking to sell that and get a mid-full size sedan (NO compacts/hatchbacks). What would be the most comfortable and fuel efficient?
Added (1). Some of the cars I was considering:
-Ford Fusion
-Ford Taurus
-Mercury Milan
-Ford Five-Hundred
-Cadillac DTS
Added (2). Unfortunately, I can't afford something new.
Added (3). I'm also thinking about the Lincoln Town Car.

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