K.T.
Here's an alternative if you are interested. I bought an Ipod nano, a workout arm band and a set of travel speakers. I put the nano in the arm band and the arm band around the travel speakers. I download movies/tv from itunes to my ipod. It is the perfect size/weight for my toddler to hold and watch in the car/plane and it is small enough I can throw in the diaper bag all the time. Obviously, the screen is small -- so if you want it to work for both your girls -- may not be your solution. Also, you wouldn't have to get the ipod -- you could get one of the cheaper off brand versions.
I have been using this for a year. The arm band protects the ipod so it still looks/acts new.