Um, WRONG, I still use carto's every day. Here's a picture of my carry around box, there's two carto's in tanks in there along with 3 filling type drip tips and a punch. (As well as some other less desirable vaporizing items but I want to make sure of the world stops tuning I can still turn PG/VG into steam)
I still use them too on occasion. Do you know how to do a Hot Swap?
ETA: You need a case for those batteries. Having them loose in there with metal is a bad plan.