round LE!
Absolutely you must round this LE on the Edge 540 Profile. That is a key design parameter and directly affects the transition stability between high alpha 3d flying. Thanks to the above posts for great answers to why this is important. It's interesting to note that pattern guys invented the shapr LE at the tip (not the root) many years ago to aid in predictable snap roll initiation and termination. During snap rolls the wing tips are stalled!