I agree with your premise. Therefore why would the airlines move towards an embedded system when they know that in the long run a portable would be far cheaper and more marketable. Easier to change out as well as improved models are offered.

They have the current phone ayatem to compare, most would prefer to use their own portable.

It wouldn`t matter if it was owned by the airline with a rental charge or if the individual brought his personal player on board and the airline charged for downloading content.

I don`t understand why they would prefer moving in the direction of embedded while the portable seems to have all the advantages and flexibility including installed cost.