I'm through episode 6, and finding this a really interesting show to watch on a meta level. As everyone knows, most Stephen King movies are ####. Yes, Shawshank is good*, but that's not what people think of when they think of Stephen King. The Shining is okay, but that took Kubrick to accomplish, and IIRC King himself would have ruined it.
Obviously Stranger Things takes a whole ####load of stuff from Stephen King, mixes it up in a 1980s blender, and pours out the resulting slurry in a highly-competent fashion. This series is the answer to the question, "What if they made a Stephen King movie with good writing, good direction, and good acting?" Strangely, the answer is that it would still suck a little, because Stephen King's stories are terrible. Every character is either irredeemably evil or has a heart of gold -- there's never any in-between. As soon as you meet a 12 year old D&D-playing nerd, you know he's going to be a heroic figure. You know the class bully isn't just a regular bully who bullies little kids, but is actually a would-be murderer who is willing to commit multiple felonies by holding a knife to some kid's throat while forcing another to commit suicide. And of course the loser small-town sheriff is going to be the guy who really gets to the bottom of things. JFC I'm rolling my eyes just typing this.
This whole story so far is a gigantic cliche that may have worked okay back in 1983 but is harder to pull off in a post-X-Files, post-Sopranos, post-Breaking Bad world where people have grown accustomed to little winks of irony and characters that aren't so predictable and black-and-white.
Like I said, I'm only halfway through, so if there is some big plot twist where one of the characters suddenly becomes something other than a cartoon, I will revise my take accordingly. This is kind of disappointing otherwise though.
* Edit: For full disclosure, I find Shawshank enjoyable to watch, but it suffers from the same problem of every character being either angelically good or diabolically evil. I've always thought it was highly overrated for that reason.