I find this odd or maybe it's just me. I have a iclear 30 (dual top coil) and I purchased a Aspire ET S BDC at the convention this past weekend. I've been vaping on the Aspire going on 7 hours now (1.8 ohms @ 4V) and the e-liquid hasn't dropped in the tank that much. If it had been the 30 (2.2ohms @ 4v), I'd have vaped about 1/2 to 2/3 of the tank by now.
Is it me or does the Aspire not use as much liquid as the 30? I mean, looking at it, it doesn't but just seems strange. Am I loosin" it?? 
