So I finally got to try one of the cartos I had filled yesterday but the results weren't great.
I did exactly what Deback suggested but they don't seem to produce any vapor compared to my regular modded carts.
Are cartos just not for me? Should I just stick with my carts for now?
When cartos are filled with the right amount, it can take a few primer drags (like 3 to 6 drags) before you'll get much vapor. Also, like LowThudd said, if you overfill a carto, it will take a while before you'll get much vapor, because you have to vape long enough to burn out the excess liquid. The inside of a carto needs to be able to breathe (needs air) to work properly.
What mixture did you put into the carto? And what percentage of VG?