I've experimented with 1.5, 2.5, & 3.0 ohm Smoktech DC cartos, but the 2.5 seems to work best so that's mostly what I've been using. But I'll be using the 1.5's because I am sitting on a supply of them.
The 3 ohm ones appear just a little to much R, I checked the math and they max out at about...