"The replacement reservoir (which was also supplied by Spring) was less comfortable to use than the original Medtronic reservoir because it does not hook on to the insulin vial. But the infusion set itself made me very happy. It’s excellent. The set comes with a built-in inserter (yes I know the Medtronic Mio has this too), which is a one button release system, so much easier to use than the two button system. The inserter mechanism is above the adhesive so you first stick the infusion set where you want it and then you release the needle."