Yes, this is sort of a n00bie question.....but I'd thought putting it out here for everyone else. I'm running with 3 Subtank Mini's with 0.5 ohm coils. I, on average, go through a tank of juice a day. Just over a week of use, sometimes 10 days, I get a hit like your sucking on heated up stainless steel (Is that known as a "dry hit"?) once in a while, even with the tank full, half empty etc. I always think the coil is used up and change it. With that yucky stainless steel hit, to me, thats always a good indication to change to coil. Am I right? Thoughts?