So I just got my other subtank mini (newest black version) a couple of days ago and also ordered an extra 1.2 and 1.5 vertical OCC heads. I started using the .5 vertical OCC that came with it and have absolutely no problems at all with it. The problems start only when I use the 1.2 and 1.5 ohm heads, I get that nasty dry burnt taste no matter what wattage I am vaping at (even as low as 15). The first couple hits are usually ok but then if I hit the vape more, I repeatedly get the burnt/dry nasty hit. This only happens with the 1.5 and 1.2 ohm heads. Does anyone else have the same problem? I even tried putting extra juice on the cotton and coils before I use it to no avail, constant dry/burnt taste after another. Never happens with the .5 ohm heads though. I'm using an istick 50w to run the subtank mini which I'm sure doesn't matter, thanks for your help and advice in advance.