I remember when I built my first mech and used cartos back then I believe was 2.2-2.4 ohm lowest they had back then was around 1.6ohm. Loved the vape I got from it. I'll try and get those old vids I took of those mods. Think I had a 901(can't remember what they were) carto and a 510. But nowadays I wouldn't be able to vape on those again, wouldn't be satisfying to me,but they were a lot better than what was out at the time