I'm not optimistic about getting a reply as this board seems to be falling into disuse. Plus, I searched and found similar questions that never received replies, but here goes anyway ....
LV offers at least 4 tools for finding straight edges, Edge Tool 3, Rake 3, Find Straight Edges 3 and Find Edge. As others have commented, the Vision Concepts manual is of no help in choosing between them. So, does anyone have any advice or experience to share regarding when to use these, and which work better or faster than others?