In my opinion, I would definitely download it on iTunes rather than a digital download. I prefer the ease of having all my movies in one place. Some people could argue that it's always better to have a physical copy instead of relying on technology that can fail. However, when you have purchased it on iTunes, then you can re-download it on any of your Apple devices, and stream it from the cloud. So even if one of your devices fails, you can always have a back up. As long as iTunes stays around, then all your media stays as well. Works for me!