Great question!
The New Type replaces both Amazonia I and Amazonia II and exceeds the performance of both due in large part to developments in the manufacturing process.
Basically it has hard grain shells similar to Amazonia I, which previously were not able to be applied to Amazonia II - the harder shell with the higher nutrient composition used to contribute to the initial water cloudiness burst.
So essentially, now with the harder granule shell, the high nutrient content of Amazonia I, and the ability to keep the water clear like Amazonia II, as well as reduce the pH like Amazonia II did (Amazonia I could always reduce water hardness, just not as much as Amazonia II), the NEW Amazonia basically offers the best of both worlds.