Ive been continuing my research. Even though this is not something I want to develop myself. Much rather have someone approach me to do it on the farm we are setting up.
It seems that the primary factor in determining anti microbial activity of honey from Leptospernums is the genetics. Soil quality, water availability also have effects but genetics are the primary factor.
Australia has Manuka native to our wetter forests but we also have many more species of Leptospernums that have much higher microbial properties (two to four times) than Manuka.
NZ might have the lead on market penetration with Manuka but Australia has access to superior plants. Mind you as a nation we seem to stuff up opportunities like this on a repetitive basis. For example Australian Red Claw (QLD yabby) industry is stuff all riven by internal rivalries and has stagnated without any leadership or support. Various opportunities where government support could have kick started the industry were never taken up Federally or at a state level. Now the largest population of Red Claw is the domestic population in the United States and will soon be over taken by domestic population in South East Asia. I can see the same thing happening with Leptospernum honey.