Theoretically, a dual coil should last longer. The reason is that inside, there are two coils, each of them with twice the resistance of the whole carto. They are burning at a much lower wattage and temperature than if it was a single coil carto.
This theoretical advantage is also the reason I don't care for them in a PV that doesn't have 4 volts or more available.
A dual coil produces more vapor, but it's cooler vapor. If you have a 1.5ohm dual coil, you will get vapor similar to what you would get if you vaped two 3ohm cartomizers at the same time. Slightly warmer than that but, in effect, that's exactly what you are doing.
At 3.7 volts, a 1.5ohm single coil carto will use 9.12 watts. A 1.5ohm dual coil will have two 3ohm cartos, each using 4.56 watts. If you bumped the voltage up to 5V, then the dual coil would be burning at 8.3 watts per coil. That would be a great vape, but you'd also be drawing 3.3 amps, which is beyond the current rating of a lot of batteries and devices.