I'm surprised that so many members here are blithely unconcerned about the possibility (nay, probability) that their purchases will disappear, sooner or later.
Anything from Sony is gonna be DRM'ed out the wazoo. Think you're going to be able to make back up copies of your movies for safekeeping? Need you be reminded of a little past history?
- Rootkit fiasco
- Bad sector copy protection
As to the last mentioned, a few of the major studios have stuck their toes in the water with a couple releases. Otherwise, it's all Sony releases. The point being, Sony is really serious about anti-copy protections, and keep upping the ante. I can't imagine it's going to be easy to defeat the protections they'll use for 4k movie downloads.
Personally, no backup, no sale. Hard drives fail, no exceptions.
Okay, I'll confess. I still have a grudge against Sony for their proprietary memory sticks. I had a rather expensive Sony camera a while back and...oh never mind.