I think the best Episode I is Q2's (aka. Thunderclap's). The reason for this is that though L8wrtr's edit is good, in various places where the dialogue is missing, there seems to remain a time where the dialogue could have been spoken which leaves one thinking something was removed from that space. In short, the periods where there was dialogue cut need to be tightened up. Q2 does this wonderfully. Seciors' edit was very well done as far as story, but there are places where he takes a word or two of dialogue from one place in the film and puts it in the middle of another scene, and the inflections sound like they don't quite match.
The best Episode II is L8wrtr's. Q2's comes in at a very close second, but L8wrtr's edges out in being slightly better at handling the love story. It's hard to say specifically what is different for me, as I haven't compared them scene for scene. It's more of a feeling I get between the characters. Seciors' is ambitious, but again the dialogue edits in places are a bit noticeable and jarring.
The best Episode III is Q2's because although Kerr, L8wrtr and Stankpac want to have Palpatine reveal his "Sith form", the implementation they use just doesn't work very well at all given the available footage (cut to Palpy who looks normal, then to Anakin/Windu, then back to Palpy who is inexplicably wrinkly.) Also, L8wrtr wants to keep Yoda from using a lightsaber, so he creates a wtf moment where Yoda is in danger and then is inexplicably not anymore.
Further, Q2 (Thunderclap) does all he can to remove R2 and 3PO from the prequels, and while I was skeptical at first, it really really does help the story a lot.
