Thanks for your replies, fellas. I'm trying to replace my cig smoking with vaping and I usually smoke Marlboro Lights and I'd prefer mouth-to-lung, so as far as I understood I should've gone with high-resistance coils (>1 Ohm) and 6mg juice... 18mg juice on 0.5 Ohm OCC with lungs inhale is really hitting me... Since 0.5 Ohm is the only resistance offered for iSub tanks I probably should start browsing for a tank which supports higher resistances... I posted my question on ECF too and copy/pasted text of the post from there. I didn't know how active people are on these vaping forums...