Many passthroughs (especially those with no inline battery) cannot provide the amps you'll need to run dual coils... They suck down tons of power very quickly (as your battery life will attest to!) The biggest USB power adapters I've seen available only supply 2.1 amps, at 5 volts (what most passthroughs run at) you are pulling 2.5 amps with a 2.0 ohm dual coil carto. You can slide by with a 2.5 dual coil, but it is a weak vape (on passthroughs, due to insufficient amps) in my experience.
If you enjoy the dual coils, and are looking to change batteries less often, I suggest an APV with an 18650 battery in it (the ones I use are 2000mah, and I use 1-2 batteries a day).