So I want to try to post my impressions.
I played through the game twice, first on normal and on hard and have completed it 100%. I played through on a 970 overclocked, i5-4690K overclocked to 4.6GHz, 16GB RAM, and SSD. I played through at 1080p30 no reconstruction all settings on high, it consistently looked amazing. So, that's the good part. Playing the game in a liner fashion (ie: start to finish using only 'continue' in the menu) with those settings works fine but keep in mind usage of all resources was very high. I'm skeptical of the game running well on lower systems mostly because CPU and RAM usage were very high regardless of settings.
However the game still has rough edges and reproducible crashes. Most notably the phone/earpiece bug and the video streaming.
The first bug is that the characters earpieces become disconnected from their bodies and float around jiggling in the air, this can also happen with phones as well. This is very annoying and happens throughout the entire game.
Secondly as I've mentioned before streaming video is broken/inefficient. I assume that if you have the bandwidth for the full 4K video streaming is fine, however if you don't the game often gets stuck trying to load a higher stream then your connection can handle causing stuttering/constant buffering. This was very frustrating, it's clear that on my regular ADSL2 connection the video was constantly buffering back and forth between 1080p and 4K. It was effectively broken and totally un-watchable. However, I was able to workaround this by running a Netflix stream in the background. Doing so forced the quality down but largely stopped the buffering (it would buffer around 4 times an episode rather than every 2 seconds). A much better solution would be to allow people to download the videos in advance or simply set a maximum quality for the streaming video.
I can reproduce crashes in 2 ways. At first I wondered why digital foundry had so many crashes on a 970 while I had none but now it's easy to understand.
Firstly, set any setting to ultra. This causes a driver crash instantly for some reason. I didn't get these crashes because I didn't set anything over high at first. Secondly, the game will crash when loading levels through the timeline. I discovered this when trying to test if I could get 60fps. Performance noticeably drops in the second level loaded through the timeline and then crashes on the third. This is strange as playing the game through normally doesn't result in crashes but manually loading levels through the timeline is broken and will cause crashes very quickly. This made it impossible for me to accurately test the performance of different settings and so I just gave up. I imagine this is what digital foundry experienced as well.
Overall the game is still fundamentally broken in many ways but works if you have very powerful hardware and are willing to accept limitations. I don't recommend trying on weaker hardware than a recent i5, 16GB of RAM and a SSD. It's possible you could get away with a lower graphics card using reconstruction and lower settings though. I was unable to really test this because of the crashing when loading levels through the timeline.
I hope the remaining issues are patched out. Microsoft really should be making this a priority, it's supposed to be a flagship product and is sold at a premium price on the market. If you accept limitations and throw powerful hardware at it it does work though.
I appreciate the work Remedy has done so far. I am trying to read between the lines and assume they have had their hands tied but I could of course be wrong. I would love to see the quality of this port match the excellent Alan Wake port. To me the difference between that port being available DRM free and it's stellar performance and this UWP locked port seems to me to be down to the publisher and it's frustrating. Of course this is my reading of the situation, I'd love any feedback on the reality that I'm not aware of.
Lastly I took some screenshots to show off how incredible it can look despite its problems. I'll embed a few or you can view the gallery as well. These are 1080p, high settings, reconstitution and film grain off. (Gallery contains spoilers)
https://flic.kr/s/aHskzPP5Yx