What I'm really interested in is what each particular author brings to the table, style- and idea-wise. What are some specific adventure bits (encounters, plots, foes, etc) that they've written that you think stand out most? Who's great at evocative descriptions? At original and fun NPCs? At traps that the players will actually appreciate getting hit by?
Thinking about your question, I realize that I don't judge adventures that way. Some really bad adventures might have some very good individual parts. But when you actually play through them, the experience is not really all that special.
The authors I listed I like because when I play through their adventure, the whole thing works to produce a fun experience.
James Jacobs (Burnt Offerings, etc.) - Burnt offerings works really well as an adventure and a setting. Taken individually, the NPCs are nothing special but you still end up caring about them and the Town of Sandpoint. It is the sort of adventure that creates memories. It has spawned a cult following of Golarion goblins and even had a high-school play written and produced based on it.
Jason Bulhman (Crypt of the Everflame) - Crypt of the everflame is a good introductory adventure. It has a decent storyline but it also has a nice basic premise suitable for introducing players to the game.
Stephen Greer (Tower of the Last Baron) - Tower of the Last Baron is a spy adventure, presenting a challenge (take out the Baron), a town, a keep, and no set method by which the adventure has to be accomplished. It is a very nice mini-sandbox adventure.
Richard Pett (Skinsaw Murders) - In the Logue versus Pett war, I tend to prefer Pett. Pett is just a very capable adventure crafter capable of delivering some captivating scenes. Yet the scenes blend well into the whole, making his adventures fun to play. Skinsaw murders is a nice combination of haunted house/mystery and though the last fight is a bit overpowered, the whole thing is pretty fun.
Nicolas Logue (Hook Mountain Massacre, Edge of Anarchy) - Nicolas Logue is better than Pett at producing disturbing images. I don't think, however, his adventures hold together in quite the same way that Pett's do. Nevertheless, if you want evocative gore, Logue is your man. The Hook Mountain Massacre is a good example of this, with its inbred ogres and ogrekin.
Eric Mona (Howl of the Carrion King) - I tend to prefer Jacob's adventures over Mona's but only just. Howl of the Carrion King is a very good adventure, one without any large dungeons. The Pugwampis make for a memorable foe and the adventure is open ended enough to allow for multiple solutions and outcomes.
Gregg Vaughn (Shadow in the Sky, Varnhold Vanishing) - Vaughn's adventures are consistent. I don't remember any of them being exceptional in any one spot and yet they are almost always well worth reading and playing.