We converted our house over to CFL's when we moved in 4 years ago. We haven't had one fail yet. I have enough stock that I don't expect to have any bulb purchase for another 5 years assuming the CFL's continue to work fine. My problem with LED's is that you are shifting from operating expense to capital expense. In this case reliability is the number one thing that can turn it from a good investment to a poor investment. One bulb failure in X (would have to calculate X based on the various costs) can mean you just lost your savings vs CFL. Too many people have had some failures with LED's to lead me to believe that their reliability is high enough to make the final payoff worth it.