That is, never beat a reigning champion (ie. winning for a vacant belt wouldn't count). I'm going to throw Dio Hurtado's name in the ring. Mixed it up with half a dozen champions-at-some-point (two HOF), and a handful of very good journeymen. Fair longevity. Last great win was Bailey, but one of only two to ever stop him (other was Cotto) and did so closer to Bailey's prime.
two strong names are david tua and juan lazcano. somebody said rocky jaurez in another thread which is another equally great mention.
Juarez is a good mention for now, but he could very easily scratch his name off the list in a couple months. :deal
Cotto gets ragged for only picking up vacant belts (and, getting ridiculously pedantic, Clottey had been stripped).
Interesting...his defenses are mostly all world-class, though. Technically, he does meet the criteria and it'll be hard to find someone else meeting them with a better resume. :think