?Thing is I see all kind of sugar amounts coming past
coming past from 1 sugar to 1 fruit to 2 sugar to 1 fruit (by weight)
So I figured 1:1 will probably work but will not be sweet enough for most people (bitter rind, peel etc)
It's also about the temp and sugar concentration to get a good set/gel. When you use less sugar you may not get that thick gel consistency which is why people sometimes add pectin. Adding pectin will give you the thick gel consistency but not the shelf life which sugar gives. I've had marmalade that has kept for many 10+ years before being opened. It's also about acidity and sugar combo.

