I would say that Planet of Judgment was the better of the two novels released at the time (the other being Marshak & Culbreath's The Price of the Phoenix), but only about average for the Bantam era.
Oh, I disagree. I'd say it's one of Bantam's best, second only to David Gerrold's The Galactic Whirlpool
. Of course, that's faint praise, since most of Bantam's output wasn't that great, and I'm sure PoJ is below Haldeman's usual level. But while not perfect, it's one of the more intriguing concepts that Bantam did, it shows a good grasp of Trek continuity and characters (though it adds some things that Trek didn't have but arguably should have, like body armor and better military procedure for landing parties, reflecting Haldeman's own military experience), and it delves more into the characters than most of the Bantams did (for instance, giving us our first prose portrayal of McCoy's divorce, though it had been addressed earlier in two issues of Gold Key's ST comic). Its main drawback is that it introduces a number of supporting characters (including a roman a clef
of James Blish), sets up a romantic triangle among them, and then seems to forget about them in the last half of the book.
World Without End fell into the period when Bantam had fallen into a rut, and literally every other novel was garbage on the theme of "Kirk leads a landing party on a visit to a primitive society that turns out to be something other than what it seems," and while it was arguably the best of the four novels on that theme, it wasn't especially good, and wasn't especially true to the Star Trek milieu.
Well, a lot of the elements of that "milieu" that conflict with the book weren't established until after it was written, so I think that's a little harsh. It wasn't a great book, but it had some interesting worldbuilding and made a decent attempt to flesh out Klingon culture, just in a different way than later creators did.