If you do manage to squeeze a dual coil into that little RTA, your issue is going to be keeping the resistance high enough to fire on a 30w istick. It'll fire down to .3 ohm but even at 30w that only gives you 3 volts, therefore it'll be a long ramp up and your battery life will also suffer. If you really want to run dual coils, get a high gauge wire to keep the resistance up closer to .5 ohm. Keep the coils as symmetrical as possible and just remember that whatever the resistance is on a single coil will be half when you install dual