Leptospermum Scoparium is found mainly in NZ. In OZ, it is found all over Taswegia, parts of NSW and in VIC; the Grampians, East Otway ranges, East Gippsland. It likes rocky, sandy sites near water. It is very similar to L. Continentale.
Id reckon all Leptospermums would have the same heralded properties as Manuka Honey. Its like you said though. Honey that is cold filtered through a coarser filter than commercial blended honey has heaps of beneficial properties in it anyway.