The movie definitely does not follow the novel to a tee, which may upset fans of the novel as it did King. I do tend to agree with King that his interpretation of Jack as a good guy who slowly devolves over the course of time is not really borne out in the movie. Nicholson never really gives off a vibe that he is a "good" person, and about 45 minutes into a two and a half hour movie, he is already going nuts. Duvall's character was not exactly written as a strong character as she was in the book, and Kubrick totally changed the ending. That said, I do think Kubrick did a perfect job with his interpretation of the story and got great performances from all the characters, including Danny Lloyd, who did a great job for being so young. Nicholson nailed the "nuts" Jack Torrance and you totally could buy that he was off the rails, even if he did not have the kind of progression the character in the book did.
The 4k set is a two-disc set containing a UHD disc and a regular Blu-Ray disc. The A/V quality in UHD is outstanding, especially the visuals at the beginning of the movie on the drive to the hotel and the exterior shots of the hotel. Most of the extras are on the regular Blu-Ray disc. The audio commentary track on the movie by one of the camera operators and Kubrick's biographer is included on both the UHD disc and the regular Blu-Ray disc. The remaining extras include a making-of documentary, which was filmed on the set by Kubrick's daughter, and a featurette on the composer who discusses the music used to score the film. There is a lot of good bonus content, but it does not include the theatrical trailer, which was included in the original DVD release.
Overall, I cannot say that the movie is for everyone. It is very violent, has a lot of swearing and some nudity in it. So, if that turns you off to a movie, then don't even think about this. Also, those who are huge fans of the book may not like Kubrick's adaptation. But, if you can look beyond those things, and are a fan of horror movies, especially those that do not involve an unstoppable killer, this is definitely worth checking out.