Absolutely fantastic experience. Loved every moment of it and I wish there was more to play. Great environments, intriguing story and some decent scares too.
For those wondering about the launcher and the game files, the launcher seems to download and install the game (around 5gb) to a folder in your appdata/local/temp folder for some reason, but don't let that put you off experiencing a great game. I hope the devs will allow us to download the game files directly in the future.
Also, keyboard+mouse didn't seem to work for me, so it looks like you NEED to use a controller.