The Italian OC groups are a more "mature" form of organized crime. They are more diversified and more entrenched in the legitimate society in Italy. The Colombians and Mexicans certainly have plenty of legit interests as well but they have always been extremely dependent on the drug trade, relatively speaking.

Before the 'Ndrangheta started forming partnerships with the cartels to bring cocaine to Europe, the Sicilians had formed partnerships with the cartels involving both heroin and cocaine.

In addition to the 100-200 'Ndrangheta members and associates cited by the FBI, there are also said to be nearly 200 Camorra affiliates, and "very few" Sacra Corona Unita members. The FBI website also cites 2,500 affiliates in the U.S. but that number has always seemed rather high to me.

I've read some reports that LCN families have begun to form connections with Mexican DTO's, like they had with Colombian DTO's in the past. As a source for drugs, of course.