It's fine. Nothing special, but nothing wrong with it either. The Predator visits Mega-City One and kills some punks, then decides that killing Judges is more fun.
Cue sixty pages of violence. Depth? Nope. Dredd getting to be cool? Surprisingly, not as much as you'd think. He's a lot of fun in ep.1, but by the end Wagner's practically turned the Predator into the story's mute, inscrutable anti-hero. It's very, very tough. It takes out a lot of opponents, including lots of Judges and two war droids. Single-handedly, of course.
There's no dramatic final kill. Instead, the Predator fires a stolen Lawgiver, which of course blows up as per standard Justice Department user identification. Psi-Judge Schaefer explains afterwards that that been suicide. The Predator had been dying, so had wanted to go down against the strongest opponents it could find. (Yes, Schaefer. She's the great-great-granddaughter of Arnold Schwarzenegger's character in the 1987 film.)
Dredd administers a coup de grace, obviously, but against an opponent who'd just committed suicide. If you're looking for cool Dredd violence, actually, ep.1's your best bet. Judge Dredd's violence is better than that in ordinary comic books, because we know he's a bastard who'll kill anyone at the drop of a hat. His introduction to the Predator here is "HIGH EXPLOSIVE!" BDAM BDAM BDAM BDAM. If he says, "Control, I got a slight problem here!" this will be as he kicks the Predator in the face.
The art's slightly cartoonish in the early pages, but it gets more atmosphere once we're into the abandoned blocks and industrial hellholes of Mega-City One. You wouldn't catch me chasing a Predator in there.
Schaefer's a little unconventional. She's not a full-time Judge, so she's happy to tell Dredd to go spin and doesn't just click her jackboots and follow orders like other Judges.
Overall... it's okay. Predator stories are less interesting than Alien stories. They degenerate more quickly into an extended macho duel, whereas an Alien story tends to focus more on its human characters and their often sinister motivations. I don't mind this three-parter, but it's nothing particularly special and I wouldn't say it's worth seeking out. It does its job. It almost hero-worships the Predator, in an odd way. It has the odd bit of nasty John Wagner dialogue, though.
"I don't see no casualties. I like ta see casualties."
"Least the driver slowed down ta let us get a good look."