In the past I have not had good luck refilling HP ink jet printer cartridges as they leaked pretty badly. However, I have always had great success 100% of the time using new HP ink cartridges, and these were no exception. My printer is back in use with great success.
I always buy an extra 2-pack in case either one of my printer black or Tri -color inks get too low to print. Buying the combo is more economical for me.