I have a Vision Viva Nova 2.5 with three eGo Twists on the way and am armed with the handy-dandy Safe Vaping Power Chart. However, I don't know if all the heads, 1.8, 2.4 and 2.8 ohm, would be appropriate and safe to use with the Twists.
Also, why would one use one ohm choice over another? Are...