Yesterday in my mail I got the latest Hard Style from DD and there was a full page of DD comrades explaining why KB's trump DB's. (Coach Rut's blog had a little thing talking about this).
Some of these things were the most ridiculous reasons ever!
My wife and I own a few DD KB's at my place but I never bought into the "KB's are better for everything hype." I personally like KB's for swings better than DB's because of the feel. I also prefer doing high rep snatches with a kb rather than a DB too.