I'm not a Horror guy by any means. If not for capeshit, it would be my least liked genre.
I think of horror like comedy. What one person finds humorous, another might not. Same for the subject of what frightens us.
That said, if I had to make a pick, I'll take Jacob's Ladder. Psychological horror does more for me opposed to monsters and this is a story that gets under the skin. This movie kept me thinking about it weeks after I had watched it (how I judge if a movie is good or not). It touches on psychological trauma and the things we don't forget, past pain that haunts us years down the line. It's inspired by the biblical story where the title is from, metaphorically retelling the story even though the ending feels a bit out of place (much of the Vietnam subplot in general could be cut out and make the movie better).
Bruce Joel Rubin wrote Jacob's Ladder. I think he's more known for writing Ghost, which was Patrick Swayze's best movie. He would go on to write another horror movie 'Deep Impact', that I think was the start of the disaster movie phenomenon going into the 2000s.