Headrest or overhead screen?

We are getting ready to purchase a 2015 Chevrolet Tahoe LT 4wd and can't decide between the DVD players and screens you can get in the headrests from the factory or the regular one that comes with the Sun, Entertainment, and Destination package. I like the fact that my kids could watch two separate moves or the same one depending on what they want to do with the headrest units. However, I'm concerned about being able to control them from the front seat while driving as easily as I could with the overhead mounted one. Which do you have and what are the pro's and con's?

I don't have an LCD screen installed in my SUV. I get dizzy from watching while the vehicle is moving. I suck.