Smoktech
does do pre-punched cartos (for their own
tanks). However, with the flange on those cartos and the height of the hole, I find that they can't be used in some other
tanks (the hole winds up covered by the tank cap). I also don't like the size of the hole they do, too small for my thick juices
A lot of vendors that sell
tanks punch or slot some for sale that way. This is a great option for those who don't have the knack or desire to do it themselves, and another benefit is that the holes will be in the right position to fit their tanks. They're slightly more expensive due to the extra labor involved, though
For me, I'd rather do the punching myself. That way they are done in the size, number and location that
I want ;-)