Nope, but he beat an ATG in Carlos Zarate and in most peoples eyes beat and got robbed against another ATG in Azumah Nelson, fighting him in his 4th weight class. Come back at me when Gamboa has done anything remotly close to that.
In fairness zarate was way past his prime and was out of boxing for over 7 years, I'll not count that victory as you do. The first fight against Azuma he could have being the winner, but in the rematch the older warrior show him who the boss really was.
While this is true, Gamboa hasnt done any of this. Fenech was a 3 division champ, and even tho he lost his rematch against azumah, he still did enough in the eyes of many, to become a 4 divsion champ. Not trying to knock on Gamboa or anything but i feel its still too soon to compare him to someone like Fenech IMO.