the other issue with reusing a needle to draw out the product is that it will start to really tear up the rubber stopper and risk having pieces of rubber fall into the gear. this would cause you to have to get a fresh sterile empty vial and a whatmann filter and filter all the remaining gear into the new sterile vial, which will cost you funds and time while doing it. not worth it considering the cost of 100 extra 18g pinzs is less than the cost of a sterile vial & whatmann filter plus a 10ml syringe to help do the transfer with.