Cuper saw this thread and sent me more information about Yonetics. This is what I understood:
Yonetics is the direct descendant of the Duncan affiliate in Mexico. The Duncan yo-yos were made in the plastic factory of somebody by the name of (Reifron ?) Briton. After many years there was no agreement on the terms of renewing the contract and he decides to make the yo-yos and tops on his own. To avoid been sued by Duncan, he changes the name for the brand to Yonetics but continues using the same molds, etc. In charge of Yonetics was Raul Juarez, who had been a Russell Coca-Cola demonstrator (together with José Barroso, the founder of 5 Estrellas). When Juarez (who according to Cuper was a very good manager) leaves to start his own brand (he died last year), a Colombian named Manuel Carmona remains in charge of the brand.
The brand currently has promotions limited to a few cities and has a small market share, but Briton's parent plastic company is still very important in the state of Nuevo León (Monterrey).