I've got 3 subox Minis, all bought from the same place, at the same time. One has been used every day, the others were still new in the box until today. With my used one, after I build the coil and put it together, it reads .5 ohm just fine. But I can take that tank and put it on the unused box mods and they both read .33 ohms. Is there a connection problem or is it possible that I got 2 counterfeit mods?