I'm waiting for underwater. I guess I won't be able to follow the thread due to spoilers as they will lag behind speedsubs.

But for your information, they release in HEVC, main10 profile, with high bitrate average. That's why the image looked so clean even in speedy/detailed/low light scenes. There are 20mbits/s spikes in the intro.
That's great, because that means it's almost as good as an high quality raw, without the weight.
And my mid-highend 2008 processor deals with it easily.

As for my impressions of ep1, they are in the season start thread.