I see two separate questions here, one being the more general "should people bring kids with cf into the world?" and "as a person with CF would you have a kid with cf?" It's the second one that I find more complicated.
I don't regret being born, nor do I regret being born with cf. I don't think that a kid with cf would have such terrible quality of life that they'd be better off not being born. There are much worse fates.
But if I found someone with whom I wanted to have children, and then I found out that he was a carrier, would I take the risk? On one hand I always think, who better than a CFer to have a kid with it, at least we kind of know what they're going through. But on the other hand, I hestitate because a kid with CF needs parents who can be there for him/her, and I worry that when my health is failing I will not be able to give that child or young adult all the care they deserve. This is NOT to say that I think kids w/o cf are perfectly self-sufficient and that if their mom is off dying, no biggie, they can take care of themselves. That's certainly not the case; I just think that if I couldn't be there for a kid with cf it would be a bigger failure.
Anyway, there are no easy answers, and I respect the people in this thread who've had the guts to be honest.