Dobson's book seems like a straight ripoff of King's bestseller; I only bought it for its cover (kid with bowl cut, check) and its ad absurdum title. I mean, virtually every single creepy kid book could be called that; it's like titling your horror novel Good Versus Evil or Scary Monster or Do Something Stupid and Die. Ugh.
Campbell's eighth novel has some respectable blurbs on it and seem like it'd be a decent read but I really think I prefer his short stories. Compare this cover to The Nameless or someone else's work of flaming youth, Audrey Rose.
The only of these that I have read is Firestarter, King's sixth published novel. I've always thought of it as a lesser novel of his, though I'm sure it has its fans. The paperback cover art is the same as the hardcover, which I like. King has said that during the late '70s and most of the '80s he was writing books like it, Cujo, Christine, and The Tommyknockers, et. al., while drunk or jacked up on cocaine and therefore doesn't remember actually writing them at all (why, those are the same reasons Drew Barrymore doesn't remember making the movie, haw-haw). I myself recall almost nothing about reading it, so I guess we're even.
Michael Whelan's cover for the 1980 limited edition hardcover