I'm not a fan of the carts that have a silicon membrane that doubles as a rubber band; it's not consistent for long tattoos like gerardcon mentioned, and the membrane lets the needle grouping flop around in the nozzle of the cart, where as the carts that have a rubber band or silicon o ring, it pulls the grouping to the bottom of the nozzle. I don't know, I'll try out TS carts...grudgingly.