I see that the grande is rated at 2.6 ohms, but I have been running it at at least 5v. It doesn't perform well at all under 4.2v (but at 5v it's wonderful). I'm fine with that since my PV goes to 6v, but it's odd because my extreme giant is rated at 2.8-3.0 ohm, and it runs fine at 3.7v. In fact, anything above 4.2v is too hot for me. Is this just because my grande is new, or is it something about the double wicks?