My favorite cartomizer for the Ego are the Boge LR (2.0 ohm). These produce a nice warm vapor with lots of flavor and a mild to medium TH.
They will last quite awhile if kept fairly wet. Typically after about a week the draw becomes stiff due to liquid carbonizing on the wick. I have cleaned them by soaking them overnight in 90% isopropyl alcohol and then rinsing with hot water(they will need to dry for a few days). This works well but I usually just toss them and grab a fresh one.
I have never had any battery problems using 2.0 ohm stuff on the Ego
batteries if anyone was wondering.
Oh btw you can find these at litecig,
madvapes and also Altsmoke (Yeti branded) as well as other places I'm sure. I have dealt with these companies and find them to be excellent.