Hi Euforeik and welcome to ECF.
Cartomizers are fine, but you can't be too cautious with them. They have to be constantly kept moist lest they will burn! You need to top them off, rather than refill, early and often.Cartomizers are disposable; they are only good for ~6-10 ml of ejuice--after that they need to go. If you like cartomizers, I suggest you look into carto-tanks, they are very nice with cartomizers because they keep them moist. But they are fiddly.
If you want something easy--just fill, tighten the connections and vape--I recommend one of the eGo-threaded bottom or top coil changeable clearomizers like T3, MT3 and eVod (bottom coil) or T2 (top coil). They were designed especially for eGos (and any of eGo clones like Vision Spinner) and they generally perform very well--once you've learned how to use them correctly.
Good luck and happy vaping!