From what I've always been reading, soft wax contains less carnauba content for ease of applying and removing. Hard wax contains a bit more carnauba (more carnauba content leads to a harder wax).
I personally use both. I have the hard candy pot and rain forest rub pot. The pot lasts a really long time, so if you don't wax like crazy or do family cars, id suggest the 30ml mini pot. Using a foam applicator will greatly reduce over-use
Hard goes on before soft. Therefore the soft wears away first and you have a fresh coat of hard goes underneath. This extends use overall
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