Chuck is a great dude all around and he was also a real fighter who went like 30 wins back in the day even beating Lews, there is some video of his early bouts, he was silent but methodical.
Another great was Joe Lewis, never met him but I know Superfoot (Bill Wallace), and Bill said he was an animal, a great great fighter and a great friend.
Bruce didn't do competitive fighting, but strictly was on form and style, he was on another level like others have mentioned. I spoke to one person who saw him at a meet in CA back in the day, and they said he saw him use a 3 inch punch with incredible force in a demonstration. They also said he didn't have a large crowd around him, people knew who he was, but that that time his fame wasn't like it was after his death. On screen, Bruce is the most fun to watch and he was incredibly fit and had mastered his body by the time of his death. When he does that side kick in Enter the Dragon, he broke a couple of that guys ribs.
Chuck and Bruce did fight in Way of the Dragon (film), but if they would have competitively fought, Chuck would probably have won because he was so skilled in it. Lee's fame has morphed into a mythology all on it's own.