I saw the original back when it came out as a kid (thanks to my mom not caring about me watching it with her ), and in a sense, I'm "completing the story's arc" by seeing it again as an adult. Anyway, it's kind of odd for me to give a review to a movie like this, because I'm really not a fan of horror movies. My biggest problem is that they don't scare me, so I don't see the point in watching them. So, for me, I need to watch a horror movie for other reasons such as interesting and/or suspenseful scenes. Similar to what I've seen some reviewers say, this isn't really as much of a horror movie but more of a horror/suspense. You're really watching characters be afraid of creepy things more so than being in something scary. A good example of that would be the first time Mike sees Pennywise, which wasn't scary at all.
I think my favorite part of the movie was the creepiness of Pennywise in this one. "Pop! Pop! Pop!" I mean... it's no Tim Curry, which might be a good thing for some people, but I do think they did a good job taking the character in a different direction. I do agree with some reviews that I've watched that parts of the movie felt kind of odd. The weirdest was probably the rock fight, which I would've expected in something like Scott Pilgrim vs. The World. I think that scene should've been done a bit differently to not be so tonally different than the rest of the movie. Mike was also pretty useless in this movie. It also ignores some of the weird, out-there aspects of the book, but it does add little easter eggs referencing them.