I'm a fan of Bob Shaw, and I'm glad he had success with the Orbitsville series. Unfortunately, I'm sorry to say the the longer the series went, the weaker it got.
Orbitsville itself was a simple story with a big idea. Departure was a more complex story about a man with a small idea - vengeance. It falls apart toward the end, when Shaw pulls the deus out of the machina as Orbitsville vanishes. Judgement aims to tell the other side of the story - about the people in Orbitsville itself.
While in Judgment, Shaw tells the story better, a lot of it is the same as in Departure. There's a simple man focused on vengeance, and a big mystic finale. The simple man here is just as driven, but less credible. A carefree man with a not terribly credible personality, is cheated, and becomes, suddenly a man with a totally different personality. And at the end of the novel, he changes again, in an even less credible way, just in time for the Hollywood ending. That's not to say all the characterization is weak; much of the smaller instances of it are good. But the personality changes simply don't work, which undermines the story overall.
The ending, as in Departure, is weak, and for the same reason. It feels tacked onto the story. Given what Shaw is trying to achieve, it's a difficult act to pull off, but the way Shaw chose doesn't really work. Even the base idea is not terribly new, and draws from Olaf Stapledons Star Maker.
This isn't a hard read. The story moves along. The protagonist is amusing, and there's a good share of humor in the story. But it doesn't all gel together well. I suggest most people stick with the first book in the series, and leave the latter two to true devotees.