I have tried so many other cartomizers because I kept reading about how great they were. I didn't like them at all, until I stumbled on these! If you aren't a fan of cartomizers, but like the idea of not having to drip as often, you must try these! I am a total convert after these and can't praise them enough! I have been using the same 2 cartomizers non-stop for 2 weeks, and they are vaping like they did when I first opened them. The flavor comes out beautifully!! Very easy draw and never feel flooded! Personally, I leave the caps off and put one of the tips from my 801 attys over it. A 510 drip tip will not fit. I filled it using the carto cap filler method (learned from doctor vapor's youtube video titled "a great way to fill cartomizers") and when it starts to run dry, I drip a few drops in the top just like you would a regular cartomizer. LOVE them!!