Like S_Trafatter said already...if she comes back scarred up, your needle was hooked and all it takes is 1. Also, I've noticed occasional needles soldered upside down to their "normal" position like all the others and in a hurry I mounted that particular grouping upside down and I don't catch it till I start color packing and wonder what is wrong. Loop your needles, you don't have to uncase them either, the packaging is clear for a reason. Older coworkers of mine would loop every new box they got, and spend HOURS doing it....but would toss out a handful every time. I just do them per tattoo.

Go low and slow. Treat tribal like yellow or white. Rotaries are the opposite of coils when it comes to saturation. The slower a rotary is, the better saturation you'll achieve. I've used a ton of needles and whatever brand you go with, stay away from bugpins. They are terrible on saturation. I threw all of mine out, that's how much I hate them. They can barely (hit or miss) do great gray shading. Also, from experience, Mithra's tight liners are made with these tiny bugpin needles that I struggle with. Kingpin's tight liners are made with a much larger bugpin, kind of in between a standard bugpin and a standard needle, and trust me, they make a world of difference when it comes to one pass saturated perfect lines.

Hope this helps you out.