Hey, so I was viewing another forum or two about sub-ohming and wasn't able to add comments? Anyways, I quit smoking almost a full year ago and went straight to vaping cold turkey... A heavy smoker I was at a pack n a half a day, I've always vaped high nic levels, 20 mg plus, but recently discover a lot of better premium flavours only available at 3 or maybe 6 nic... So I found a place that sells 100mg/ml nic flavourless and add a tiny bit to each 3 mg juice..(about 5mls of that brings a 30ml mix up to 20mg) Anyways, also started building my own Delta 2 RBA coils out of fused Clapton wire and getting builds between .25 and .8 ohms depending on size, wraps, etc. And I have no problem vaping for a couple days, borderline chain vaping, at 20mg high VG at around 35 to 45W... Have friends who dabble in vaping, and I told them you need More nicotine if you were or are a heavy smoker as each cigarette has 1mg per so a pack has 20 to 25! Simple math... this all works for me