The funny thing is that I used one for years and I found that it actually hurt less than injecting manually. Insulin syringes today are a lot smaller now though and thankfully disposable. It seems bonkers now looking back that you used the same steel needle for years until it bent and stopped working! I remember taking the glass syringe in it's container with me to Alton Towers and going on all the rides.That's as close as I EVER want to get to 1
Having recently switched to 8mm disposable syringes from 12.7mm, these are a lot easier too.