I'd be saving movies onto the laptop, carrying the proper USB cables and saving them off onto devices rather than carrying an extra gadget.

I use Azul on my iDevices - it plays most formats, and doesn't need me to do the iTunes dance. It also has a built in web-server and download ability.

e.g. my iPhone has a movie I want to watch on my iPad, so I setup a Personal Hotspot on phone, and enable the webserver in Azul. Connect to the hotspot, fire up Azul on the iPad, download it from the phone's Azul webserver and a minute later I have it transferred and can watch it (and turn off the phone, not have to worry about streaming and continued battery drain)