Originally Posted by Prime
Based on what? Grievous is neither Jedi or Sith, and he is one of the most deadly users around. At a time when Kenobi and Yoda are the only Jedi left, he says that lightsabers are still used in some galactic quarters. They are obviously not Jedi. Kenobi also hands his father's saber to Luke and isn't all "OMFG be careful with that!"
Well both of your examples were either trained in Jedi arts or soon to be so, so there's not a lot that your point is based on either. What I'm saying is that the lightsaber is a tool of the Jedi/Sith, and they use lightsabers because in a Jedi's hand they become much more powerful and useful than they are in most, where normally, it would be little more than an oversized light up tin opener.