I had my babies all micro-chipped so that if they were to ever get separated from us and their ID tags, there would be another form of identification on them. We camp and travel a lot and they go everywhere with us- I know how quickly accidents can happen or unplanned events... this is just another way to put us at ease.
By the way, even though it is a larger needle- my babies didn't make a peep when they got chipped. I was so worried before it was done, turns out it was no big deal at all!