Lithium Ion batteries, be it in an ego, a riva, an 18650, a stacked set in a 6v mod, are all 3.7 volts nominal, but around 4.1v fully charged.
So here's the fun part about battery longevity... They have a mah value, which is a measurement of it's total capacity, in terms of ma over one hour. The more current you draw the faster it will drain. This is not completely irrelevant to its maximum output capability at any given time. So, a device designed to run at 3.7v will have just as long of a life as the 6v mod equivalent, assuming an equal amount of power is demanded, which will depend on the resistance, as well as the efficiency of converting the voltage.
So, in general, a variable voltage mod will be the least efficient, per mah of the battery, and a small unregulated battery will be the most efficient, but quite possibly sag in voltage, thus not outputting what you ask of it.
So, the resistance of the atty or carto you use will directly modify the drain regardless of what you place it on, unless a device can't supply the maximum output, at which point it drains at a lower rate. If this goes too low, you can damage the battery though, which is why very low resistances should only be used on batteries that can handle the output required.
In a nut shell, yeah, the resistance of what you put on the device can make a 3.7v/3.2v seem like a 6v mod. It doesn't drain faster, it's just that most people think of 3.7v as a low end device, where in reality all lithium ion batteries are 3.7v, no matter what fancy nickname the mod has.
There's a bit more to it, but that's enough for now.
//I like variable voltage too. But there's no way I'm going to carry my provari everywhere. Thing weighs a ton.
