Oh for sure Draug. I wasn't meaning to even discuss which was _better_, just which author (if either) created a more obsessively developed universe. For example, 1984 is a great work of literature, and it would not make sense to say it is better or worse than the other two, but you could unambiguously say that Airstrip One is not as highly developed a place as either the Dune universe or Middleearth. So it's a different thing.
That said, I did have a little bit of trouble just now thinking up an alternate-world that is both very good and not highly developed. I was going to use Narnia, e.g., but although it's not as developed as the others, I wanted something more ambiguous, because it is, at least, somewhat developed. Ditto for Ender.
I wonder if it's hard, once you've created a completely different world, to reign in your own curiosity about everything about it.