There're a couple of huge downsides (for me personally) to streaming services that just grinds with me:

• the quality is always worse than physical media, and
• scrobbing (moving back and forwards in the video, with the arrow keys or by moving the playback head) is almost never instantaneous, it usually requires a couple of seconds while the video rebuffers

Perhaps physical media is better these days (than DVDs were) for scrobbing, but then you have the FBI piracy messages to deal with. I've never owned a BluRay player, perhaps they're better?

But I know that sailing the high seas gets me a high-quality video, and I can jump backwards ~5 seconds instantaneously when I've not heard a bit a of dialogue.