Preferably, you want 2.0-3.2Ω... so what you're using looks OK to me. I tend to use 2.2-2.7Ω with eGo batts.
I'd recommend you try them with a 1.8 ohm coil though - even without Variable Voltage, you'll get more oomph from an Ego with a lower resistance coil.
...., I guess it's all a matter of taste.