I had a chance to shoot all the trigger Tech triggers at the show this week. They have a single stage and two stage for the Excalibur. I much prefer the two stage trigger over the single. The single stage just breaks clean. The two stage has a slack that you take up, then it hit's a "wall". You then pull through the wall to break the shot. I fell the two stage has a much better feel to it.
The Parker model is a single stage and it's one of the best triggers I've ever experienced on a Parker bow. The Ten Point/Wicked Ridge trigger is a single stage as well. These triggers break clean and have very little creep. You must concentrate to feel them creep! If a light trigger is what you are after Trigger Tech has the trigger that will take care of it.