You've asked four questions. Let's address them one at a time. [I've taken the liberty of converting your single sentence into several separate ones and threw in some punctuation. Hope you don't mind.]
1. Is it cheaper to buy the e-liquids over the ready-to-go carts?
Yes. Unless you decide to drip (directly onto the atomizer), you also will need a few
blank cartridges, which you can refill many times. To me, the even more persuasive reason to fill carts yourself with e-liquid is the
much greater selection of e-liquid (PG or VG, purity level, flavors, nicotine levels). [NOTE: That second reason also applies to cartomizers, but less so: there are a great many choices in cartomizers these days.]
2. How may packs do you get out of 1 cart? [NOTE: In Australia the average pack of smokes is 25.]
Actually, it's the other way around: How many carts are equivalent to one pack of 25 analogs? That is, carts don't last as long as you thought. Off hand, I'd say two to five. It varies depending on your e-cig model: super-minis and some of the minis have very small carts, penstyles have fairly large carts, and cartomizers effectively cram more e-liquid into their medium size than most carts. [To clarify: The carts themselves will last for a
long time. The filler will need to be washed or replaced every day or so. What will have to be replaced two to five times to be equivalent to 25 analogs is the e-liquid.]
3. Do the flavored carts or e-liquids have tobacco in them?
There is
no tobacco in any e-cig cartridge or e-liquid. However, the nicotine is
extracted from tobacco as are the tobacco flavors. A zero-nicotine non-tobacco flavor (e.g., chocolate mint, one of my favorites
) should never have been within spitting distance of a tobacco leaf.
4. Can you buy bigger carts to fit more liquid in?
Most e-cig models have only one size cart that fits. Recently, TECC and Totally Wicked came out with MEGA carts (used with MEGA atomizers) for their Titan-branded Joye510 model.
