spirit for lining not good to line with a spirit you need to alter your technique you need to pull instead of push the line and you need to run it fast which if your line me and have a slow hand for lining it doesnt feel right thunder is a better liner you can go any direction or speed and it wont snag in the skin and because of the more powerful motor you can feel the power and feel what you are doing its great and for solid colour in difficult places its a god send for sure.. if i want colour blend or do black and grey spirit if i want solid lines and to pack colour in like a bitch thunder