I don't know why the prefilled cartridges/cartomizers sometimes taste different. I have a feeling that perhaps they've sat for a while so have developed better flavor. I'm pretty sure most prefilled cartridges and cartos are prefilled with Dekang liquid. The bottle of Tobacco you bought is likely Dekang as well, but maybe it just isn't old enough to have developed a better flavor. Let it sit for a while (to steep) and maybe visit it again after several weeks. I have liquids from Dekang that were awful when I first bought them... over a year later I've tried a few again that just sat in a box, and they have surprisingly changed to a better flavor. Hopefully, you won't have to wait for a year. LOL
For sweeter tobacco flavors you can buy now: I recently tried some Vaper's Choice Honey Tobacco and it was awesome (ecigsupply.com). Vapor4Life's Kant has a sweet honey background. DIY Flavor Shack Honey Tobacco has good reviews too.
Normally, I vape a non sweet tobacco all day like Smooth 8 (bit of ginger to it and nice throat hit) or Freedom (almost a cedar back flavor) from Halo, but recently received a 10ml sample of their Tribeca (just a light hint of sweet caramel but not overpowering like some RY4). Good stuff!
Sweeter smoking tobacco is typically sweetened with honey so a plain bottle of Honey e-liquid could sweeten up any tobacco that you have now and isn't sweet enough. Even the Dekang Honey liquid is the Bee's Knees
. Just go lightly when adding it to a small amount of the tobacco liquid you've put in a separate bottle until you find a good ratio and know that it will work for you. After that, mix the rest.
Really good honey e-liquid can be found from this vendor:
http://www.vsvapor.net/personal-vaporizer-Honey-108 and also from
Honey E-Liquid and other vendors on the forum which you can easily find threads by doing a search for honey through the forum search or look for honey e-liquid on Google search.
