Technically under a gigabit, and the same is true almost up to 4 streams, but that's just copy time. Once it's there, the bandwidth between storage and instances would easily meet that requirement, then all you need transferred back to your end is the current image / audio. Still, as much as I hate to say it, residential internet speeds are still outrageously slow, variable, and expensive, but I'm just speculating about the future for fun right now. (If you're working in a studio, I would think it'd be less outlandish to find those speeds to the wide web, but I'm unsure of your current setup) 16 GB of RAM for video editing / compositing (Not trying to talk down, just unsure if the "video" prefix is applicable or redundant to the latter). Fair enough :PRed Raw, at 4k, is 36MB/sec.
"At least 16GB for compositing?" I don't even know what that means.
We're friends. Which is why I say, with affection, "you're talking out of your ass." I'm not. Don't make us both upset by deliberately misunderstanding things I do for a living to make a point you can't support.