ok well let me start off by saying i bought the 510 and didn't buy any fluid. was tottally a newb still am and figured oh well if i don't like it in going going to waste my money on fluid to boot..well i got those carts and they taste HORRIBLE...then i ran out, and i went to pilot to buy joys refill carts. those are about 5 times as much flavor of death then the carts i was given so im thinking at this point vaping just isn't from me idk how juices could be soo much better then the carts since i just really want tobacco and that's it. now the maybe stupid/smart thing i did was add root beer flavor concentrate a drop to my lil cartridge. now these things taste a million times better but im not to sure if its the greatest thing to vape root bear concentrate lol..but anything beats those carts BLAH hoping the juice i got from freedomsmokeusa is better then this cart crap. but anyways if your stuck with carts you might wanna drop in a flavor and it seems just fine then