hope this is not a dumb question, just a few weeks into the e-cig, started with Smoke51 Duo cartridges,I like the coffee flavor,, then got a 510 unit with liquid drops,also coffee flavor,,I was using both but find myself more into the 510 unit with drops, even tho you have to re fill every once in a while,and sometimes is a little messy? its more of a real smoke hit, more intense, I stocked up on 3 packs of cartridges so have to use them, but any thoughts on whats better? more economical? more popular? sorry if some of my terminology is newbie-ish thank you for all the help and info
