So I just recently purchased the smok TFV4 and wanted to use the .15ohm coil head that it came with in my penny mech mod. I'm using brand new LG HE2 batteries. Basically I was a little worried that it might not be safe. I tried using one of those Ohm's law calculators and was even more confused afterward. Am I safe to use this setup or should I go a bit higher on the ohms. I used the .2ohm coil head it came with for the past several days with no issues.