Nice to see people still adding to this. I definitely feel along the lines that lower voltage/wattage/heat is better for harshness. I also have an update about using PEG-400 as the solvent: it gets harsher over time. It's a strange thing. The solution starts as a light yellow, but over time it has become a darker red, like the color you see with the PG solutions (and becomes as harsh as them), and in the ecig it has become a very dark red. Kind of strange.