I considered pet insurance briefly, but I know the pedigree of my babies from the breeder and they have given me confidence that their bloodline is of good health. I still looked into it and ended up deciding that I'd put aside money each month instead, praying my babies will never need it and being extra cautious on everything to make sure they don't injure themselves.
Here's an interesting read on whether or not this writer thinks it's worth it:
Is Pet Insurance Worth the Cost? - Consumer Reports