At his best, he was a very good fighter. However, I don't think his career was that great if you compare it with other lower weight fighters. He was a level below the likes of other multi-weight champions from the same divisions, and against the best fighter he fought - Ioka, he was thoroughly outclassed. Not to mention, he exploited the WBO rule for moving up in weight, which made it easier for him to win titles in more weight classes.
He literally and figuratively punched above his weight. Always was a flawed talent who brought everything he's got: he's the least skilled 4 division champ of all time. But that's not criticism, it's admiration, he's achieved far more on guts & hard work than most with better natural gifts.
He did alright against Ioka when he wasn't getting bounced off the canvas. He was just too open but he shaded some rounds at least.