I have both the Edge Pro and the KME. The KME offers, IMO, a significant advantage over the Edge Pro in that you don't have to hold the knife with your hand. Holding the knife while using the Edge Pro is fatiguing and introduces a variable that makes sharpening more difficult. It also requires you to be ambidextrous, which I'm not. The KME holds the knife for you which minimizes error. The KME can be used while watching TV while the Edge Pro requires you to be at a table or bench. The KME is significantly cheaper as well.
Just my .02.