I got my first carto tank with a two hole carto. I used a 50/50 liquid it didn't wick well, so I tried slotting and that was a disaster. I would rather get prepunched cartos. I found three hole cartos and they're great, but they aren't as common as two hole cartos. I prefer vaping at higher wattages, and it kills my cartos faster than I'd like. I found a couple high resistance cartos but they only come with two holes. I prefer 70/30 anyway, but I found out I can't even tolerate 50/50 liquids (coughing fits) so now I only use 70/30 or 60/40. Does anyone have issues using liquids in that ratio with two hole cartos?