Best Digital Platform for TV Shows Not Available on Blu-Ray

[cicada88]

I'm looking to buy a couple of series that will likely never see a Blu-Ray release. I almost never buy any movies or TV shows digitally, so I'm pretty uninformed on which platforms are considered the best.

I mainly want the best Video and Audio quality, but I also need to be able to freely play, take screen shots, and video clips from the videos. AKA, I don't want to be locked to any platform.

The 2 main series I'm interested in are The Americans (Seasons 1-6) and Halt & Catch Fire (Seasons 1-4). I think both of these had only had the 1st season released on Blu-Ray unfortunately.

I'm sure this is somewhat a show by show decision as I know iTunes has some exclusives etc, but in general what is considered the best platform?