I think that makes a huge difference. If you know a book, huge changes/things left out bother you, when you haven't you can just watch it as something new.
That's half the problem with some people on remakes and book movies. To tell you the truth I take not a grain of salt on most reviews especially rotton tomatoes, not singling them out just I watch and love many poorly rated movies. Sometimes I think it's better to just watch it as if it's new, never watched the previous or read the book. I've seen the trailers and previews on Dark Tower and it looks pretty good, I actually can't wait to watch it, been reading the books since I was a teen over 20yrs ago, probably closer to 30yrs ago.
Many movies people are not happy when they change some aspect of them, the Dukes of Hazzard movie many fans hated, I'm a fan also and the movie was not the same, but I think it was a great movie, same with the newer Karate Kid, not Karate was kung fu and Jackie Chan ain't no Mr. Miyagi, but still a very good movie. Still haven't watched Mad Max Fury road, big Mad Max fan, I hope it's good, I'll probably like it if it isn't true to the original series, and Ghost Busters, haven't saw the new one yet either, we just recently had free HBO and they had it on, I missed it but DW started watching it and turned the channel, I was outside busy, she said it was terrible IDK? I'll probably still watch the whole thing and like it Lol! The newer True Grit...good movie but...I hated Jeff Bridges fake accent of growly....John Wayne didn't sound like that, only thing that turned me off, if he didn't fake grrowlllcoughcough was a great movie.
I actually can't wait to see Dark Tower, really looking forward to it.