I always thought that it was important to decide whether the tests would change anything. Like, loads of people have had Down's babies and said they wouldn't have changed anything and the kids grow up happy, etc. I guess CF would be pretty yucky - especially with the life expectancy. Personally I'd have all the tests, but that's just me. I guess that's why they have a counsellor to help you decide!
ANYWAY...these babies have got such good karma (or is that the huge amounts of prayers being sent up for them? ) they'll be fine. And Carol's right....they are going to have so many godmothering people!