I'm just amateur for this time, but I understood a lot of amateurs and professionals are using these type of grip without using autoclave. I would like to go for those, but I'm scared to use it due to cross contamination, do you use some produces to eliminate or reduce the risks of contamination? If you take the cartridge from the back without paying attention and then lock in into the grip there is a risk of contamination, that's why I ask you that.
I use cartridges with an rpg grip. Im always scared of contamination issues and since I dont have a autoclave machine, I make sure to clean the grip with detol, then with pure spirit and then with water before every tatttoo. Just with a piece of paper.
As for the cartridges, If your workstation is clean and your table has been wiped clean before the tattoo then I dont think its too risky to keep them on the table and switch between them.
If you want to be completely safe then you can place something clean and put each cartridge in there until you switch again.