$20 is spent on craftsmanship. These are Americans working hard to make a living and in turn pouring that living back into OUR economy. You're buying the tank itself generally with a set of guts. The guts are replaceable - the tank will last you. Meh.
I mostly use 80/20 or 70/30. For some reason I tend to taste VG, so if I go any more than 30% I start to taste it. 80/20 and 70/30 seem to be the most popular.