Managed to get about 5 hours in on this last night, very impressed with it so far, the attention to detail in the graphics is mind blowing and those hardworking folk at Rockstar should be very proud of the final product. I've got through the first chapter in the snow and I'm now at the Horseshoe Overlook camp trying to figure out what to do next to start earning money for the gang. I went on a grizzly bear hunt with one of the other guys which ended in a savaging very reminiscent of The Revenant, but I managed to beat the bear with a knife as it was pinning me down in the end. Also ended up in a typically wild west bar fight in the town of Valentine with chairs and tables flying all over.
I bought the hard copy so installation only took around an hour and a half from two discs, but 105gb is the largest game file I've ever had to install, had to delete a few other games from my PS4 to fit it on!
Whilst most people are loving the game, I've seen some comments from people complaining that you spend a lot of time just riding through the countryside on horseback, but in a world as stunning as this one I don't see that as a bad thing and there is plenty to do.