I've just started playing around with the iJoy RDTA combo. Built a coil, not very pretty but works. Used 26ga kanthal with 6 double wraps and put in two coils. I'm using an iJustS which has a 3000mA battery and runs at about 50W. Regulated device. Although it works, it seems to take a while to fire up. Tried removing one coil as you can build single coil set ups, but still seems sluggish. Any ideas where I'm going wrong? Kind of have to pulse it a few times then take a pull.