hi! so i've been pretty busy and not had time to comment until now...having probs with the machine. i've only used it on two tattoos. the first time was excellent, had a surprising amount of give to the feel while lining...only prob i had was the machine would occasionally stop running. since it ran as soon as the needle was removed, i put it down to the resistance of the return setup inside the cartridge being a bit much for the motor. workaround when it happened was undoing the cartridge, then refitting it. this worked fine for the first tattoo. the next time, i had already used the workaround method twice, and all of a sudden there was a high-pitched squeal from the motor and no movement at the needle. during partial disassembly i was able to establish and repeat the noise/problem. applying the slightest of pressure to the white plastic piston this occurs, and the gear it is attached to stops spinning while the one directly out of the motor spins freely. this seems to fit with my thoughts on the resistance of the cartridge. all that said of course, we have a problem if the gearing/motor can't hold up to the resistance of the cartridge it was designed for! i'm using genuine cheyenne hawk cartridges.